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Which country is highlighted?
[ "Saint Kitts and Nevis", "Barbados", "Dominica", "Antigua and Barbuda" ]
3
closed choice
grade6
social science
geography
The Americas: geography
Identify and select countries of the Caribbean
This country is Antigua and Barbuda.
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Which of the following contains a vague pronoun reference?
[ "Though Mr. Nelson loved the old house's charming kitchen, it was in serious need of repair.", "The old house was in serious need of repair, but Mr. Nelson loved its charming kitchen." ]
0
closed choice
grade7
language science
writing-strategies
Pronouns and antecedents
Identify vague pronoun references
When writing, make sure to avoid vague pronoun references. A vague pronoun reference occurs when a pronoun could refer to more than one possible antecedent. When Lisa and Kim finally landed, she breathed a sigh of relief. The pronoun she could refer to either Lisa or Kim, so the meaning of the sentence is unclear. Vagu...
The first answer choice contains a vague pronoun reference. The pronoun it could refer to the house or the kitchen. Though Mr. Nelson loved the old house's charming kitchen, it was in serious need of repair. The second answer choice shows a possible correction for the vague pronoun reference. The text has been rewritte...
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Is grooming a dog a good or a service?
[ "a service", "a good" ]
0
closed choice
grade2
social science
economics
Economics
Goods and services
Everything you can buy is either a good or a service. A good is something you can touch or hold in your hands. For example, a hammer is a good. A service is a job you pay someone else to do. For example, cooking food in a restaurant is a service.
To decide whether grooming a dog is a good or a service, ask these questions: Is grooming a dog something you can touch? No. Is grooming a dog a job you might pay someone else to do? Yes. So, grooming a dog is a service.
Which country is highlighted?
[ "Tonga", "the Marshall Islands", "Vanuatu", "Tuvalu" ]
0
closed choice
grade7
social science
geography
Oceania: geography
Identify and select countries of Oceania
This country is Tonga.
Compare the average kinetic energies of the particles in each sample. Which sample has the higher temperature?
[ "neither; the samples have the same temperature", "sample B", "sample A" ]
1
The diagrams below show two pure samples of gas in identical closed, rigid containers. Each colored ball represents one gas particle. Both samples have the same number of particles.
closed choice
grade7
natural science
physics
Particle motion and energy
Identify how particle motion affects temperature and pressure
The temperature of a substance depends on the average kinetic energy of the particles in the substance. The higher the average kinetic energy of the particles, the higher the temperature of the substance. The kinetic energy of a particle is determined by its mass and speed. For a pure substance, the greater the mass of...
The particles in both samples have the same average speed, but each particle in sample B has more mass than each particle in sample A. So, the particles in sample B have a higher average kinetic energy than the particles in sample A. Because the particles in sample B have the higher average kinetic energy, sample B mus...
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Which greeting is correct for a letter?
[ "Dear Uncle adam,", "Dear Uncle Adam," ]
1
closed choice
grade2
language science
capitalization
Capitalization
Greetings and closings of letters
A letter starts with a greeting and ends with a closing. For each one, capitalize the first word and end with a comma. You should also capitalize proper nouns, such as Aunt Sue. Dear Aunt Sue, I'm glad you could come to my party, and thank you for the birthday gift. I could not have asked for a better one! Every time I...
The first greeting is correct: Its first word is capitalized, and it ends with a comma. Uncle Adam is capitalized because it is a proper noun.
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What do these two changes have in common? making jam a slice of banana turning brown
[ "Both are caused by heating.", "Both are caused by cooling.", "Both are only physical changes.", "Both are chemical changes." ]
3
closed choice
grade8
natural science
chemistry
Chemical reactions
Compare physical and chemical changes
Matter is made of very small particles called atoms. Atoms can be linked together by chemical bonds. When two or more atoms link together, they form a molecule. In a chemical change, the chemical bonds in the molecules break. The atoms then link together to form different molecules. The types of molecules in matter bef...
Step 1: Think about each change. Making jam is a chemical change. It involves mixing fruit, sugar, and a substance called pectin. When these ingredients are mixed and cooked, the chemical bonds in their molecules are broken. The atoms then link together to form different molecules that make up the jam. A slice of banan...
What is the probability that a sheep produced by this cross will be homozygous dominant for the fleece type gene?
[ "0/4", "1/4", "3/4", "2/4", "4/4" ]
0
This passage describes the fleece type trait in sheep: The fleece, or outer coat, of a sheep is often cut off and used to make yarn for fabrics and other textiles. Woolly fleeces, which have shorter hairs, are usually used for clothing and blankets. Hairy fleeces, which have longer hairs, are usually used for carpets. ...
closed choice
grade8
natural science
biology
Genes to traits
Use Punnett squares to calculate probabilities of offspring types
Offspring genotypes: homozygous or heterozygous? How do you determine whether an organism is homozygous or heterozygous for a gene? Look at the alleles in the organism's genotype for that gene. An organism with two identical alleles for a gene is homozygous for that gene. If both alleles are dominant, the organism is h...
Which better describes the Gobi Desert ecosystem?
[ "It has dry, thin soil. It also has long, cold winters.", "It has heavy snow. It also has only a few types of trees." ]
0
Figure: Gobi Desert. The Gobi Desert is a cold desert ecosystem in northern China and southern Mongolia.
closed choice
grade4
natural science
biology
Ecosystems
Describe ecosystems
An environment includes all of the biotic, or living, and abiotic, or nonliving, things in an area. An ecosystem is created by the relationships that form among the biotic and abiotic parts of an environment. There are many different types of terrestrial, or land-based, ecosystems. Here are some ways in which terrestri...
A cold desert is a type of ecosystem. Cold deserts have the following features: a small amount of rain or snow, dry, thin soil, and long, cold winters. So, the Gobi Desert has dry, thin soil. It also has long, cold winters.
What can a seed grow into?
[ "a fruit", "a flower", "a new plant" ]
2
This tomato has seeds inside.
closed choice
grade4
natural science
biology
Plants
Describe and construct flowering plant life cycles
Many plants have flowers. These plants can use their flowers to reproduce, or make new plants like themselves. How do plants use their flowers to reproduce? First, the male part of the flower makes pollen, and the female part makes eggs. Animals, wind, or water can move pollen. Pollination is what happens when pollen i...
A seed can germinate and grow into a new plant. The new plant can grow fruit and flowers. But a seed does not grow into a fruit or a flower.
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Which is a run-on sentence?
[ "The conductor took tickets from everyone on the train.", "Mabel is from Greenpoint now she lives in Springdale." ]
1
closed choice
grade3
language science
writing-strategies
Sentences, fragments, and run-ons
Is it a complete sentence or a run-on?
A sentence is a group of words that forms a complete thought. It has both a subject and a verb. My friends walk along the path. A run-on sentence is made up of two sentences that are joined without end punctuation or with just a comma. I knocked on the door it opened. It started raining, we ran inside. To fix a run-on ...
Mabel is from Greenpoint now she lives in Springdale is a run-on sentence. It has two sentences that are joined without end punctuation: Mabel is from Greenpoint and Now she lives in Springdale.
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Which logical fallacy is used in the text? Ariana's shoes are superior, because they're made from one hundred percent snakeskin, not synthetic materials.
[ "red herring: the use of a completely unrelated topic or idea", "appeal to nature: the assumption that natural things are always good" ]
1
closed choice
grade7
language science
writing-strategies
Developing and supporting arguments
Classify logical fallacies
A strong argument uses valid reasoning and logic in support of a claim. When an argument or claim introduces irrelevant information or misrepresents the issues at hand, it may be committing a logical fallacy. Logical fallacies can hurt a writer's credibility and can lead readers to draw false conclusions. A logical fal...
The text argues that Ariana's shoes are the best, because they're made with snakeskin rather than synthetic materials. However, even though the shoes are made from snakes, that doesn't necessarily mean that they are better. This illustrates a type of logical fallacy known as an appeal to nature.
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Which figure of speech is used in this text? Kaylee and Eddie had met before through mutual friends, but they had never been alone together until their first date.
[ "hyperbole", "oxymoron" ]
1
closed choice
grade11
language science
figurative-language
Literary devices
Classify the figure of speech: euphemism, hyperbole, oxymoron, paradox
Figures of speech are words or phrases that use language in a nonliteral or unusual way. They can make writing more expressive. A euphemism is a polite or indirect expression that is used to de-emphasize an unpleasant topic. The head of Human Resources would never refer to firing people, only to laying them off. Hyperb...
The text uses an oxymoron, a joining of two seemingly contradictory terms. Alone together is a contradiction, because being alone means by yourself, but together means with someone else.
Is Asimina triloba made up of one cell?
[ "yes", "no" ]
1
This organism is Asimina triloba. It is a member of the plant kingdom. Asimina triloba is commonly called the pawpaw. Pawpaw trees grow in the southeastern part of the United States. They have large, sweet fruit. The fruit is sometimes called a prairie banana.
yes or no
grade5
natural science
biology
Classification
Describe, classify, and compare kingdoms
In the past, scientists classified living organisms into two groups: plants and animals. Over the past 300 years, scientists have discovered many more types of organisms. Today, many scientists classify organisms into six broad groups, called kingdoms. Organisms in each kingdom have specific traits. The table below sho...
Asimina triloba is a plant. Plants are made up of many cells.
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Based on this information, what is this pea plant's genotype for the pea shape gene?
[ "ee", "wrinkled peas" ]
0
In a group of pea plants, some individuals have round peas and others have wrinkled peas. In this group, the gene for the pea shape trait has two alleles. The allele E is for round peas, and the allele e is for wrinkled peas. A certain pea plant from this group has wrinkled peas. This plant has two alleles for wrinkled...
closed choice
grade6
natural science
biology
Genes to traits
Genetics vocabulary: genotype and phenotype
All organisms have pieces of hereditary material called genes, which are passed from parents to offspring. Genes contain instructions for building the parts of an organism. An organism's genes affect its observable traits, including its appearance, its behavior, and which diseases it may have. Genes may have different ...
An organism's genotype for a gene is its combination of alleles for that gene. The pea plant has two alleles for wrinkled peas (e). So, the plant's genotype for the pea shape gene is ee.
Which ocean is highlighted?
[ "the Atlantic Ocean", "the Southern Ocean", "the Pacific Ocean", "the Arctic Ocean" ]
1
closed choice
grade8
social science
geography
Physical Geography
Oceans and continents
Oceans are huge bodies of salt water. The world has five oceans. All of the oceans are connected, making one world ocean.
This is the Southern Ocean. The Southern Ocean reaches from the shores of Antarctica to 60° South latitude.
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Which is a compound sentence?
[ "The artist prepared a canvas for a new oil painting.", "Devon shot the arrow, but she missed the target." ]
1
closed choice
grade4
language science
grammar
Sentences, fragments, and run-ons
Is the sentence simple or compound?
A simple sentence is a sentence with only one subject and predicate. The pitcher threw the ball to first base. A compound sentence is two simple sentences joined by a comma and a conjunction such as and, but, or, or so. The pitcher threw the ball, and the batter hit it. Some simple sentences have a compound subject or ...
The second sentence is the compound sentence. It is made up of two simple sentences joined by a comma and the conjunction but. Devon shot the arrow, but she missed the target.
Will these magnets attract or repel each other?
[ "attract", "repel" ]
0
Two magnets are placed as shown.
closed choice
grade4
natural science
physics
Magnets
Identify magnets that attract or repel
Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. Whether a magnet attracts or repels other magnets depends on the positions of its poles, or ends. Every magnet has two poles: north and south. Here are some examples of magnets. The no...
To predict if these magnets will attract or repel, look at which poles are closest to each other. The north pole of one magnet is closest to the south pole of the other magnet. Opposite poles attract. So, these magnets will attract each other.
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What does the verbal irony in this text suggest? "This is the best day of my life," Mr. Duran mumbled after his car broke down on the way to an important job interview.
[ "Mr. Duran liked fixing cars.", "Mr. Duran was having a bad day." ]
1
closed choice
grade6
language science
figurative-language
Literary devices
Interpret figures of speech
Figures of speech are words or phrases that use language in a nonliteral or unusual way. They can make writing more expressive. Verbal irony involves saying one thing but implying something very different. People often use verbal irony when they are being sarcastic. Olivia seems thrilled that her car keeps breaking dow...
The text uses verbal irony, which involves saying one thing but implying something very different. The best day of my life ironically suggests that Mr. Duran was having a bad day. He was having the opposite of a good day because his car broke down when he needed to be on time.
During this time, thermal energy was transferred from () to ().
[ "each aquarium . . . the surroundings", "the surroundings . . . each aquarium" ]
0
Two identical aquariums were next to an open window. One aquarium had a plastic cover on it, and the other was uncovered. This table shows how the temperature of each aquarium changed over 1.5hours.
closed choice
grade7
natural science
physics
Thermal energy
Compare thermal energy transfers
A change in an object's temperature indicates a change in the object's thermal energy: An increase in temperature shows that the object's thermal energy increased. So, thermal energy was transferred into the object from its surroundings. A decrease in temperature shows that the object's thermal energy decreased. So, th...
The temperature of each aquarium decreased, which means that the thermal energy of each aquarium decreased. So, thermal energy was transferred from each aquarium to the surroundings.
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What is the mass of a fire truck?
[ "19 tons", "19 ounces", "19 pounds" ]
0
Select the best estimate.
closed choice
grade5
natural science
units-and-measurement
Units and measurement
Choose customary units of mass
Measurements are written with both a number and a unit. The unit comes after the number. The unit shows what the number means. Mass is a measurement of how much matter something contains. There are many different units of mass. When you are using customary units, mass may be written with units of ounces, pounds, or ton...
The best estimate for the mass of a fire truck is 19 tons. 19 ounces and 19 pounds are both too light.
Is the following statement about our solar system true or false? Of the four smallest planets, two are made mainly of gas.
[ "false", "true" ]
0
Use the data to answer the question below.
true-or false
grade8
natural science
earth-science
Astronomy
Analyze data to compare properties of planets
A planet's volume tells you the size of the planet. The primary composition of a planet is what the planet is made mainly of. In our solar system, planets are made mainly of rock, gas, or ice. The volume of a planet is a very large quantity. Large quantities such as this are often written in scientific notation. For ex...
To decide which four planets are the smallest, look at the volumes and compare the exponents. The volumes of Mercury, Venus, Earth, and Mars have the smallest exponents. So, these four planets are the smallest. These four planets are made mainly of rock. So, of the four smallest planets, none are made mainly of gas.
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Does this passage describe the weather or the climate? It has not rained in over a week at Jaden's house.
[ "climate", "weather" ]
1
Hint: Weather is what the atmosphere is like at a certain place and time. Climate is the pattern of weather in a certain place.
closed choice
grade3
natural science
earth-science
Weather and climate
What's the difference between weather and climate?
The atmosphere is the layer of air that surrounds Earth. Both weather and climate tell you about the atmosphere. Weather is what the atmosphere is like at a certain place and time. Weather can change quickly. For example, the temperature outside your house might get higher throughout the day. Climate is the pattern of ...
Read the text carefully. It has not rained in over a week at Jaden's house. This passage tells you about the precipitation last week at Jaden's house. It describes the atmosphere at a certain place and time. So, this passage describes the weather.
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Which is a complete sentence?
[ "Kylie bought a red belt and a pink scarf.", "Her comfortable clothing and her warm coat." ]
0
closed choice
grade3
language science
writing-strategies
Sentences, fragments, and run-ons
Is it a complete sentence, a fragment, or a run-on?
A sentence is a group of words that forms a complete thought. It has both a subject and a verb. My friends walk along the path. A sentence fragment is a group of words that does not express a complete thought. It is usually missing a subject or a verb. Knows the answer. This is a sentence fragment. It is missing a subj...
Kylie bought a red belt and a pink scarf is a complete sentence. The subject is Kylie, and the verb is bought.
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What is the source of the allusion in the sentence below? After my father spoke, my mother shrugged as if to say there was no sense in trying to change an Archie Bunker.
[ "a movie", "television" ]
1
closed choice
grade11
language science
figurative-language
Literary devices
Recall the source of an allusion
An allusion is a brief mention of something or someone well known, often from mythology, history, or literature. An allusion lets you reference ideas from an entire story in just a few words. The protean nature of the disease makes it difficult to diagnose. The word protean is an allusion to the sea god Proteus in Gree...
The source of the allusion Archie Bunker is television. In the television series All in the Family, working-class patriarch Archie Bunker is known for his politically incorrect opinions. The allusion Archie Bunker means a person who holds outdated prejudices.
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What do these two changes have in common? cutting a piece of rope water evaporating from a puddle
[ "Both are caused by heating.", "Both are caused by cooling.", "Both are only physical changes.", "Both are chemical changes." ]
2
closed choice
grade3
natural science
chemistry
Physical and chemical change
Compare physical and chemical changes
Chemical changes and physical changes are two common ways matter can change. In a chemical change, the type of matter changes. The types of matter before and after a chemical change are always different. Some chemical changes are caused by heating or cooling. For example, burning a piece of paper is a chemical change c...
Step 1: Think about each change. Cutting a piece of rope is a physical change. The rope is shorter after you cut it. But it is still made of the same type of matter as the uncut rope. Water evaporating from a puddle is a change of state. So, it is a physical change. The liquid changes into a gas, but a different type o...
During this time, thermal energy was transferred from () to ().
[ "the surroundings . . . each vial", "each vial . . . the surroundings" ]
0
Scientists in a laboratory were working with insulin, a protein often used to treat diabetes. They left two identical vials of insulin in different places. This table shows how the temperature of each vial changed over 15minutes.
closed choice
grade7
natural science
physics
Thermal energy
Compare thermal energy transfers
A change in an object's temperature indicates a change in the object's thermal energy: An increase in temperature shows that the object's thermal energy increased. So, thermal energy was transferred into the object from its surroundings. A decrease in temperature shows that the object's thermal energy decreased. So, th...
The temperature of each vial increased, which means that the thermal energy of each vial increased. So, thermal energy was transferred from the surroundings to each vial.
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What information supports the conclusion that Zack acquired this trait?
[ "Zack won a competition at his school with his jump rope tricks.", "Zack's sister taught him how to do tricks with a jump rope.", "Zack has three jump ropes, each made of a different material." ]
1
Read the description of a trait. Zack knows how to do tricks with a jump rope.
closed choice
grade8
natural science
biology
Genes to traits
Inherited and acquired traits: use evidence to support a statement
Organisms, including people, have both inherited and acquired traits. Inherited and acquired traits are gained in different ways. Inherited traits are passed down from biological parents to their offspring through genes. Genes are pieces of hereditary material that contain the instructions that affect inherited traits....
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Is the following trait inherited or acquired? Kenji has five fingers on each hand.
[ "acquired", "inherited" ]
1
closed choice
grade5
natural science
biology
Traits and heredity
Identify inherited and acquired traits
Organisms, including people, have both inherited and acquired traits. Inherited and acquired traits are gained in different ways. Inherited traits are passed down through families. Children gain these traits from their parents. Inherited traits do not need to be learned. Acquired traits are gained during a person's lif...
Most humans are born with five fingers on each hand. So, having five fingers is an inherited trait.
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What does the euphemism in this text suggest? These five-inch heels make the perfect accessory for vertically challenged fashionistas.
[ "The heels are recommended for people with good balance.", "The heels are recommended for short people." ]
1
closed choice
grade9
language science
figurative-language
Literary devices
Interpret figures of speech
Figures of speech are words or phrases that use language in a nonliteral or unusual way. They can make writing more expressive. A euphemism is a polite or indirect expression that is used to de-emphasize an unpleasant topic. The head of Human Resources would never refer to firing people, only to laying them off.
The text uses a euphemism, a polite or indirect expression that is used to de-emphasize an unpleasant topic. The euphemism vertically challenged suggests that the heels are recommended for short people. Vertically challenged is a playful way of referring to someone who is not very tall.
Is the following statement about our solar system true or false? The four largest planets are made mainly of gas or ice.
[ "true", "false" ]
0
Use the data to answer the question below.
true-or false
grade8
natural science
earth-science
Astronomy
Analyze data to compare properties of planets
A planet's volume tells you the size of the planet. The primary composition of a planet is what the planet is made mainly of. In our solar system, planets are made mainly of rock, gas, or ice. The volume of a planet is a very large quantity. Large quantities such as this are often written in scientific notation. For ex...
To decide which four planets are the largest, look at the volumes and compare the exponents. The volumes of Jupiter, Saturn, Uranus, and Neptune have the largest exponents. So, these four planets are the largest. Jupiter and Saturn are made mainly of gas. Uranus and Neptune are made mainly of ice. So, the four largest ...
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Complete the sentence. Bleaching clothes is a ().
[ "chemical change", "physical change" ]
0
closed choice
grade5
natural science
chemistry
Physical and chemical change
Compare physical and chemical changes
Matter is made of very small particles called atoms. Atoms can be linked together by chemical bonds. When two or more atoms link together, they form a molecule. In a chemical change, the chemical bonds in the molecules break. The atoms then link together to form new molecules. The types of molecules in matter before an...
Bleaching clothes is a chemical change. The bleach reacts with dark stains on the clothes. The reaction changes the stains into different types of matter that wash away easily.
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Two gold bars have the same temperature but different masses. Which gold bar has more thermal energy?
[ "the gold bar with less mass", "the gold bar with more mass" ]
1
The objects are made of the same type of matter.
closed choice
grade6
natural science
physics
Thermal energy
How are temperature and mass related to thermal energy?
Matter is made of tiny particles called atoms. Atoms are always moving. The energy of moving atoms is called thermal energy. The total amount of thermal energy in matter depends on three things: the type of matter, the amount of matter, and how fast the atoms are moving. Temperature measures how hot or cold matter is. ...
The two gold bars have the same temperature and are made of the same type of matter. So, the gold bar with more mass has more thermal energy.
Think about the magnetic force between the magnets in each pair. Which of the following statements is true?
[ "The magnetic force is weaker in Pair 1.", "The magnetic force is weaker in Pair 2.", "The strength of the magnetic force is the same in both pairs." ]
0
The images below show two pairs of magnets. The magnets in different pairs do not affect each other. All the magnets shown are made of the same material.
closed choice
grade4
natural science
physics
Magnets
Compare strengths of magnetic forces
Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes between magnets are called magnetic forces. The stronger the magnetic force between two magnets, the more strongly the magnets attract or repel each other. You c...
Distance affects the strength of the magnetic force. When magnets are farther apart, the magnetic force between them is weaker. The magnets in Pair 1 are farther apart than the magnets in Pair 2. So, the magnetic force is weaker in Pair 1 than in Pair 2.
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Which text uses the word factoid in its traditional sense?
[ "The Summerfield Daily Mail was forced to issue a retraction after printing a factoid about Summerfield's founder. It turned out that the reporter had written the article based on local legend rather than researching the actual history.", "A reporter for the Summerfield Daily Mail dug up an amusing factoid about ...
0
closed choice
grade10
language science
writing-strategies
Word usage and nuance
Explore words with new or contested usages
Words change in meaning when speakers begin using them in new ways. For example, the word peruse once only meant to examine in detail, but it's now also commonly used to mean to look through in a casual manner. When a word changes in meaning, its correct usage is often debated. Although a newer sense of the word may be...
The second text uses factoid in its traditional sense: something made up presented as a true fact. The Summerfield Daily Mail was forced to issue a retraction after printing a factoid about Summerfield's founder. It turned out that the reporter had written the article based on local legend rather than researching the a...
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Select the plant.
[ "Cherry trees can grow white or pink flowers.", "Howler monkeys eat leaves, fruit, and nuts." ]
0
closed choice
grade2
natural science
biology
Classification
Identify plants and animals
Plants and animals are living things. Living things are called organisms. Plants come in many shapes and sizes. Most plants grow in the ground. They might grow leaves, flowers, and fruit. Plants cannot move around on their own like animals can. Animals also come in many shapes and sizes. Most animals can move around. A...
A howler monkey is an animal. It eats leaves, fruit, and nuts. A howler monkey's tail can be longer than the rest of its body! A cherry tree is a plant. It can grow white or pink flowers. Many types of cherry trees come from Japan. Some of these trees have flowers, but no cherries!
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What is the temperature of a cup of hot coffee?
[ "155°F", "155°C" ]
0
Select the better estimate.
closed choice
grade7
natural science
units-and-measurement
Units and measurement
Estimate temperatures
Measurements are written with both a number and a unit. The unit comes after the number. The unit shows what the number means. Temperature can be written with units of degrees Fahrenheit (°F) or Celsius (°C). Use the list below to compare the two units. 212°F | Water boils | 100°C 98.6°F | Body temperature | 37°C 68°F ...
The better estimate for the temperature of a cup of hot coffee is 155°F. 155°C is too hot.
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Complete the sentence. Blending a smoothie is a ().
[ "chemical change", "physical change" ]
1
closed choice
grade5
natural science
chemistry
Physical and chemical change
Compare physical and chemical changes
Matter is made of very small particles called atoms. Atoms can be linked together by chemical bonds. When two or more atoms link together, they form a molecule. In a chemical change, the chemical bonds in the molecules break. The atoms then link together to form new molecules. The types of molecules in matter before an...
Blending a smoothie is a physical change. The fruit in the smoothie breaks into tiny pieces, but it is still made of the same type of matter.
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Using only these supplies, which question can Samuel investigate with an experiment?
[ "Do watercolor paintings dry faster when placed next to a fan?", "Do watercolor paintings dry faster when they are placed inside or outside?", "Does a large watercolor painting or a small watercolor painting dry faster?" ]
1
Samuel is painting watercolor pictures with his friend. An hour after they have finished, Samuel notices one painting is dry but the other is not. He wonders what factors affect how quickly watercolor paintings dry. So, he decides to design an experiment. He has the following supplies available: two freshly painted wat...
closed choice
grade8
natural science
science-and-engineering-practices
Designing experiments
Identify questions that can be investigated with a set of materials
Experiments can be designed to answer specific questions. When designing an experiment, you must identify the supplies that are necessary to answer your question. In order to do this, you need to figure out what will be tested and what will be measured during the experiment. Imagine that you are wondering if plants gro...
Select the bird below.
[ "toco toucan", "rabbit" ]
0
Birds have feathers, two wings, and a beak. A peregrine falcon is an example of a bird.
closed choice
grade3
natural science
biology
Classification
Identify mammals, birds, fish, reptiles, and amphibians
Birds, mammals, fish, reptiles, and amphibians are groups of animals. The animals in each group have traits in common. Scientists sort animals into groups based on traits they have in common. This process is called classification.
A rabbit is a mammal. It has fur and feeds its young milk. Rabbits live underground in burrows. A group of rabbit burrows is called a warren. A toco toucan is a bird. It has feathers, two wings, and a beak. Toucans have large beaks. A toucan's beak can be half as long as its body.
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Based on this information, what is Boba's phenotype for the fur length trait?
[ "long fur", "short fur" ]
1
In a group of Syrian hamsters, some individuals have short fur and others have long fur. In this group, the gene for the fur length trait has two alleles. The allele for long fur (f) is recessive to the allele for short fur (F). Boba is a Syrian hamster from this group. Boba has the homozygous genotype FF for the fur l...
closed choice
grade7
natural science
biology
Genes to traits
Genetics vocabulary: dominant and recessive
All organisms have pieces of hereditary material called genes, which are passed from parents to offspring. Genes contain instructions for building the parts of an organism. An organism's genes affect its observable traits, including its appearance, its behavior, and which diseases it may have. Genes may have different ...
Boba's genotype for the fur length gene is FF. Boba's genotype of FF has only F allelles. The F allele is for short fur. So, Boba's phenotype for the fur length trait must be short fur. To check this answer, consider whether Boba's alleles are dominant or recessive. The allele for long fur (f) is recessive to the allel...
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Which sentence uses a simile?
[ "Reggie's eyes are bright green emeralds.", "Reggie's eyes are as green as emeralds." ]
1
closed choice
grade5
language science
figurative-language
Literary devices
Identify similes and metaphors
Similes and metaphors are figures of speech that compare two things that are not actually alike. A simile compares two things by saying that one is like the other. Similes often use the words like and as. My sister runs like a cheetah. The sister's running and a cheetah's running are compared using the word like. A che...
This sentence uses a simile: Reggie's eyes are as green as emeralds. The words eyes and emeralds are compared using the word as. This sentence uses a metaphor: Reggie's eyes are bright green emeralds. The words eyes and emeralds are compared without the word like or as.
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What is the source of the allusion in the sentence below? Ethan spoke at the city council meeting, claiming the new recycling regulations were draconian.
[ "a fable", "Greek history" ]
1
closed choice
grade10
language science
figurative-language
Literary devices
Recall the source of an allusion
An allusion is a brief mention of something or someone well known, often from mythology, history, or literature. An allusion lets you reference ideas from an entire story in just a few words. "I'd better get home before I turn into a pumpkin!" Lila remarked. Here, Lila alludes to the fairy tale "Cinderella," in which C...
The source of the allusion draconian is Greek history. Draco, a government official in seventh-century Athens, Greece, wrote a code of laws that called for severe punishments for even minor offenses. The allusion draconian means harsh.
Which solution has a higher concentration of purple particles?
[ "neither; their concentrations are the same", "Solution B", "Solution A" ]
1
The diagram below is a model of two solutions. Each purple ball represents one particle of solute.
closed choice
grade7
natural science
chemistry
Solutions
Compare concentrations of solutions
A solution is made up of two or more substances that are completely mixed. In a solution, solute particles are mixed into a solvent. The solute cannot be separated from the solvent by a filter. For example, if you stir a spoonful of salt into a cup of water, the salt will mix into the water to make a saltwater solution...
In Solution A and Solution B, the purple particles represent the solute. To figure out which solution has a higher concentration of purple particles, look at both the number of purple particles and the volume of the solvent in each container. Use the concentration formula to find the number of purple particles per mill...
Which solution has a higher concentration of yellow particles?
[ "neither; their concentrations are the same", "Solution B", "Solution A" ]
0
The diagram below is a model of two solutions. Each yellow ball represents one particle of solute.
closed choice
grade6
natural science
chemistry
Solutions
Compare concentrations of solutions
A solution is made up of two or more substances that are completely mixed. In a solution, solute particles are mixed into a solvent. The solute cannot be separated from the solvent by a filter. For example, if you stir a spoonful of salt into a cup of water, the salt will mix into the water to make a saltwater solution...
In Solution A and Solution B, the yellow particles represent the solute. To figure out which solution has a higher concentration of yellow particles, look at both the number of yellow particles and the volume of the solvent in each container. Use the concentration formula to find the number of yellow particles per mill...
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How long is a sunflower seed?
[ "16 millimeters", "16 kilometers", "16 meters" ]
0
Select the best estimate.
closed choice
grade5
natural science
units-and-measurement
Units and measurement
Choose metric units of distance
Measurements are written with both a number and a unit. The unit comes after the number. The unit shows what the number means. When you are using metric units, length can be written with units of millimeters, centimeters, meters, or kilometers. One meter contains 100 centimeters or 1,000 millimeters. So, 1 meter is lar...
The best estimate for the length of a sunflower seed is 16 millimeters. 16 meters and 16 kilometers are both too long.
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Using only these supplies, which question can Turner investigate with an experiment?
[ "Do cloth towels dry faster if they are hung in the laundry room or in the backyard?", "Does a small cloth towel or a large cloth towel dry faster when hung in the backyard?", "When hung in the laundry room, do black cloth towels or white cloth towels dry more quickly?" ]
0
After Turner cleans up a spill, he hangs a wet cloth towel in the laundry room. Two hours later, he notices that the towel has partially dried. He wonders what factors affect how cloth dries. So, he decides to design an experiment. He has the following supplies available: two identical white cloth towels water a clothe...
closed choice
grade7
natural science
science-and-engineering-practices
Designing experiments
Identify questions that can be investigated with a set of materials
Experiments can be designed to answer specific questions. When designing an experiment, you must identify the supplies that are necessary to answer your question. In order to do this, you need to figure out what will be tested and what will be measured during the experiment. Imagine that you are wondering if plants gro...
Think about the magnetic force between the magnets in each pair. Which of the following statements is true?
[ "The magnetic force is stronger in Pair 2.", "The strength of the magnetic force is the same in both pairs.", "The magnetic force is stronger in Pair 1." ]
0
The images below show two pairs of magnets. The magnets in different pairs do not affect each other. All the magnets shown are made of the same material.
closed choice
grade4
natural science
physics
Magnets
Compare strengths of magnetic forces
Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes between magnets are called magnetic forces. The stronger the magnetic force between two magnets, the more strongly the magnets attract or repel each other. You c...
Distance affects the strength of the magnetic force. When magnets are closer together, the magnetic force between them is stronger. The magnets in Pair 2 are closer together than the magnets in Pair 1. So, the magnetic force is stronger in Pair 2 than in Pair 1.
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Which text uses the word random in its traditional sense?
[ "At the grocery store, Christine hastily grabbed fruits and vegetables at random, filling her shopping cart with a hodgepodge of food.", "Christine made a random trip to the grocery store, though her kitchen was already stocked with a hodgepodge of food." ]
0
closed choice
grade12
language science
writing-strategies
Word usage and nuance
Explore words with new or contested usages
Words change in meaning when speakers begin using them in new ways. For example, the word peruse once only meant to examine in detail, but it's now also commonly used to mean to look through in a casual manner. When a word changes in meaning, its correct usage is often debated. Although a newer sense of the word may be...
The second text uses random in its traditional sense: made or occurring without a definite pattern. At the grocery store, Christine hastily grabbed fruits and vegetables at random, filling her shopping cart with a hodgepodge of food. The first text uses random in its nontraditional sense: odd or out of place. Christine...
Does this passage describe the weather or the climate?
[ "weather", "climate" ]
0
Figure: Lake Titicaca. Lake Titicaca is a large, deep lake on the border between Peru and Bolivia. A strong south wind blew across the water last night. Hint: Weather is what the atmosphere is like at a certain place and time. Climate is the pattern of weather in a certain place.
closed choice
grade5
natural science
earth-science
Weather and climate
Weather and climate around the world
The atmosphere is the layer of air that surrounds Earth. Both weather and climate tell you about the atmosphere. Weather is what the atmosphere is like at a certain place and time. Weather can change quickly. For example, the temperature outside your house might get higher throughout the day. Climate is the pattern of ...
Read the passage carefully. Lake Titicaca is a large, deep lake on the border between Peru and Bolivia. A strong south wind blew across the water last night. The underlined part of the passage tells you about the wind direction at Lake Titicaca last night. This passage describes the atmosphere at a certain place and ti...
Which ocean is highlighted?
[ "the Indian Ocean", "the Pacific Ocean", "the Arctic Ocean", "the Atlantic Ocean" ]
2
closed choice
grade7
social science
geography
Physical Geography
Oceans and continents
Oceans are huge bodies of salt water. The world has five oceans. All of the oceans are connected, making one world ocean.
This is the Arctic Ocean.
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Which type of sentence is this? An avid reader, Brad attends weekly book club meetings, and he finishes several novels every month.
[ "compound-complex", "simple", "compound", "complex" ]
2
closed choice
grade7
language science
grammar
Phrases and clauses
Is the sentence simple, compound, complex, or compound-complex?
A clause is a group of words that contains both a subject and a predicate. An independent clause is a complete thought that can stand alone as a sentence. A dependent clause (or subordinate clause) is not a complete thought and cannot stand alone as a sentence. the oranges on our tree are ripe The clause can stand alon...
The sentence is compound. It is made up of two independent clauses joined by the coordinating conjunction and. An avid reader, Brad attends weekly book club meetings, and he finishes several novels every month.
Which statement describes the Catoctin Mountain Park ecosystem?
[ "It has soil that is poor in nutrients.", "It has only a few types of trees.", "It has many different types of trees." ]
1
Figure: Catoctin Mountain Park. Catoctin Mountain Park is a temperate deciduous forest ecosystem in Maryland. Most of this forest was cut down for its wood in the early 1900s. But since the 1940s, conservation efforts have allowed the forest to return to much of this park.
closed choice
grade6
natural science
biology
Ecosystems
Describe ecosystems
An environment includes all of the biotic, or living, and abiotic, or nonliving, things in an area. An ecosystem is created by the relationships that form among the biotic and abiotic parts of an environment. There are many different types of terrestrial, or land-based, ecosystems. Here are some ways in which terrestri...
A temperate deciduous forest is a type of ecosystem. Temperate deciduous forests have the following features: warm, wet summers and cold, wet winters, soil that is rich in nutrients, and only a few types of trees. So, the following statement describes the Catoctin Mountain Park ecosystem: warm, wet summers and cold, we...
What type of rock is gneiss?
[ "metamorphic", "sedimentary", "igneous" ]
0
This is a piece of gneiss. Gneiss is a rock made of minerals such as biotite and garnet. The minerals in gneiss are often arranged in bands. Gneiss can form when a rock is changed by high temperature and pressure. Gneiss is often found deep inside the Earth's crust.
closed choice
grade7
natural science
earth-science
Rocks and minerals
Classify rocks as igneous, sedimentary, or metamorphic
Igneous rock is formed when melted rock cools and hardens into solid rock. This type of change can occur at Earth's surface or below it. Sedimentary rock is formed when layers of sediment are pressed together, or compacted, to make rock. This type of change occurs below Earth's surface. Metamorphic rock is formed when ...
Gneiss is a metamorphic rock. Like other metamorphic rocks, it forms when a rock is changed by high temperature and pressure. Heat and pressure can change the type and arrangement of minerals in a rock. This change forms a new rock with different properties. Gneiss can form when sedimentary, igneous, or other metamorph...
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What does the verbal irony in this text suggest? "This salsa could use a little more spice," Tristan said as he gulped down water and wiped tears from his eyes.
[ "The salsa was too spicy.", "The salsa was tasteless." ]
0
closed choice
grade6
language science
figurative-language
Literary devices
Interpret figures of speech
Figures of speech are words or phrases that use language in a nonliteral or unusual way. They can make writing more expressive. Verbal irony involves saying one thing but implying something very different. People often use verbal irony when they are being sarcastic. Olivia seems thrilled that her car keeps breaking dow...
The text uses verbal irony, which involves saying one thing but implying something very different. Could use a little more spice ironically suggests that the salsa was too spicy. Tristan gulped down water and wiped tears from his eyes, indications that the salsa was indeed too spicy.
Select the fish below.
[ "bull shark", "Hermann's tortoise", "olive toad", "horned frog" ]
0
Fish live underwater. They have fins, not limbs. Fish are cold-blooded. The body temperature of cold-blooded animals depends on their environment. A goldfish is an example of a fish.
closed choice
grade4
natural science
biology
Classification
Identify mammals, birds, fish, reptiles, and amphibians
Birds, mammals, fish, reptiles, and amphibians are groups of animals. Scientists sort animals into each group based on traits they have in common. This process is called classification. Classification helps scientists learn about how animals live. Classification also helps scientists compare similar animals.
A bull shark is a fish. It lives underwater. It has fins, not limbs. Bull sharks can live in both fresh and salt water. They are found in rivers and in shallow parts of the ocean. An olive toad is an amphibian. It has moist skin and begins its life in water. Toads do not have teeth! They swallow their food whole. A hor...
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Which word does not rhyme?
[ "wed", "fed", "men" ]
2
closed choice
grade2
language science
phonological-awareness
Rhyming
Which word does not rhyme?
Rhyming words are words that end with the same sound. The words tip and slip rhyme. They both end with the same sound. The words meet and treat also rhyme. They both end with the same sound, even though the sound has two different spellings. The words tip and meet don't rhyme. They end with different sounds.
The words fed and wed rhyme. They both end with the ed sound. The word men does not rhyme. It ends with a different sound.
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What does the idiom in this text suggest? "Speak of the devil!" Rachel declared when Felix strolled into the room.
[ "Rachel had just been speaking about Felix.", "Rachel didn't trust Felix." ]
0
closed choice
grade7
language science
figurative-language
Literary devices
Interpret figures of speech
Figures of speech are words or phrases that use language in a nonliteral or unusual way. They can make writing more expressive. An idiom is an expression that cannot be understood literally. Its meaning must be learned. The assignment was a piece of cake.
The text uses an idiom, an expression that cannot be understood literally. The idiom speak of the devil suggests that Rachel had just been speaking about Felix. People say this when the person they've just been speaking about coincidentally arrives, as if summoned.
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Select the one true statement.
[ "The Golgi directs cell activities by sending instructions to different parts of an animal cell.", "The nucleus of an animal cell does not have chromosomes.", "The cytoplasm fills and maintains the space inside an animal cell." ]
2
closed choice
grade7
natural science
biology
Cells
Compare cells and cell parts
Look at the models of molecules below. Select the elementary substance.
[ "ozone", "ethanol", "trichlorofluoromethane" ]
0
closed choice
grade6
natural science
chemistry
Atoms and molecules
Identify elementary substances and compounds using models
There are more than 100 different chemical elements, or types of atoms. Chemical elements make up all of the substances around you. A substance may be composed of one chemical element or multiple chemical elements. Substances that are composed of only one chemical element are elementary substances. Substances that are ...
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Select the plant.
[ "Moles eat insects and worms.", "Apple trees can grow fruit." ]
1
closed choice
grade2
natural science
biology
Classification
Identify plants and animals
Plants and animals are living things. Living things are called organisms. Plants come in many shapes and sizes. Most plants grow in the ground. They might grow leaves, flowers, and fruit. Plants cannot move around on their own like animals can. Animals also come in many shapes and sizes. Most animals can move around. A...
An apple tree is a plant. It can grow fruit. People have been growing apples for thousands of years. There are more than 7,500 types of apples! A mole is an animal. It eats insects and worms. Moles live mostly underground.
What is the capital of Oregon?
[ "Honolulu", "Salem", "Missoula", "Portland" ]
1
closed choice
grade5
social science
geography
State capitals
Identify the 50 state capitals
Salem is the capital of Oregon.
Which color does this map use to show land that is not covered by water or ice?
[ "green and brown", "blue and white" ]
0
This is a map of Earth. The map uses color to show where water, land, and ice are found.
closed choice
grade3
natural science
earth-science
Earth's features
Water on Earth
Many maps of Earth use color to show different areas. Green and brown show land that is not covered by water or ice. Blue shows liquid water in oceans, rivers, lakes, and other bodies of water. White shows frozen water. These parts of Earth's surface are covered by ice.
Green and brown are used to show land not covered by water or ice.
Complete the statement. 2-chloroethanol is ().
[ "an elementary substance", "a compound" ]
1
The model below represents a molecule of 2-chloroethanol. 2‑Chloroethanol is a poisonous substance used to make chemicals that kill insects.
closed choice
grade8
natural science
chemistry
Atoms and molecules
Classify elementary substances and compounds using models
There are more than 100 different chemical elements, or types of atoms. Chemical elements make up all of the substances around you. A substance may be composed of one chemical element or multiple chemical elements. Substances that are composed of only one chemical element are elementary substances. Substances that are ...
Use the model to determine whether 2-chloroethanol is an elementary substance or a compound. Step 1: Interpret the model. . Use the legend to determine the chemical element represented by each color. The colors and atomic symbols from the legend are shown in the table below. The table also includes the names of the che...
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Which word would you find on a dictionary page with the following guide words? tear - top
[ "trailer", "ticket" ]
1
closed choice
grade2
language science
reference-skills
Reference skills
Use guide words
Guide words appear on each page of a dictionary. They tell you the first word and last word on the page. The other words on the page come between the guide words in alphabetical order. To put words in alphabetical order, put them in order by their first letters. If the first letters are the same, look at the second let...
Put the words in alphabetical order. Since ticket is between the guide words tear - top, it would be found on that page.
Will these magnets attract or repel each other?
[ "attract", "repel" ]
1
Two magnets are placed as shown.
closed choice
grade5
natural science
physics
Magnets
Identify magnets that attract or repel
Magnets can pull or push on other magnets without touching them. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes are called magnetic forces. Magnetic forces are strongest at the magnets' poles, or ends. Every magnet has two poles: a north pole (N) and a south pole (...
To predict if these magnets will attract or repel, look at which poles are closest to each other. The north pole of one magnet is closest to the north pole of the other magnet. Like poles repel. So, these magnets will repel each other.
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Which logical fallacy is used in the text? In January, we opened a new prison in town. By May, criminal activity had dropped. So, the new prison must have been the reason for the drop in crime.
[ "appeal to nature: the assumption that natural things are always good", "false causation: the assumption that because two things happened together, one caused the other", "hasty generalization: a broad claim based on too few observations" ]
1
closed choice
grade12
language science
writing-strategies
Developing and supporting arguments
Classify logical fallacies
A strong argument uses valid reasoning and logic in support of a claim. When an argument or claim introduces irrelevant information or misrepresents the issues at hand, it may be committing a logical fallacy. Logical fallacies can hurt a writer's credibility and can lead readers to draw false conclusions. A logical fal...
The text argues that the new prison led to less criminal activity. However, that's not necessarily true. For instance, there might have been other factors that affected criminal activity, which were unrelated to the opening of the new prison. This illustrates a type of logical fallacy known as false causation.
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Which greeting is correct for a letter?
[ "Dear sanjay,", "Dear Sanjay," ]
1
closed choice
grade3
language science
punctuation
Formatting
Greetings and closings of letters
A letter starts with a greeting and ends with a closing. For each one, capitalize the first word and end with a comma. You should also capitalize proper nouns, such as Aunt Sue. Dear Aunt Sue, I'm glad you could come to my party, and thank you for the birthday gift. I could not have asked for a better one! Every time I...
The second greeting is correct: Its first word is capitalized, and it ends with a comma. Sanjay is capitalized because it is a proper noun.
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Compare the motion of three sailboats. Which sailboat was moving at the highest speed?
[ "a sailboat that moved 40miles east in 5hours", "a sailboat that moved 45miles north in 5hours", "a sailboat that moved 15miles south in 5hours" ]
1
closed choice
grade3
natural science
physics
Force and motion
Compare the speeds of moving objects
An object's speed tells you how fast the object is moving. Speed depends on both distance and time. Distance tells you how far the object has moved. One unit used to measure distance is the mile. Time tells you how long the object has spent moving. One unit used to measure time is the hour. Think about objects moving f...
Look at the distance each sailboat moved and the time it took to move that distance. The direction each sailboat moved does not affect its speed. Notice that each sailboat moved for 5 hours. The sailboat that moved 45 miles moved the farthest distance in that time. So, that sailboat must have moved at the highest speed...
Select the bird below.
[ "parrotfish", "porcupinefish", "Tasmanian devil", "white stork" ]
3
Birds have feathers, two wings, and a beak. Birds are warm-blooded. Warm-blooded animals can control their body temperature. A blue-footed booby is an example of a bird.
closed choice
grade4
natural science
biology
Classification
Identify mammals, birds, fish, reptiles, and amphibians
Birds, mammals, fish, reptiles, and amphibians are groups of animals. Scientists sort animals into each group based on traits they have in common. This process is called classification. Classification helps scientists learn about how animals live. Classification also helps scientists compare similar animals.
A porcupinefish is a fish. It lives underwater. It has fins, not limbs. Porcupinefish can puff up their bodies with air or water to scare off predators. A white stork is a bird. It has feathers, two wings, and a beak. Storks wade in shallow water to look for food. Storks eat fish, insects, worms, and other small animal...
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Which statement describes the canoe's motion?
[ "The canoe has a constant velocity.", "The canoe is accelerating." ]
1
A canoe is turning to the left to avoid getting stuck in shallow water.
closed choice
grade8
natural science
physics
Velocity, acceleration, and forces
Identify whether objects are accelerating
An object's velocity describes its speed and its direction. An object has a constant velocity when neither its speed nor its direction is changing. So, an object has a constant velocity when the object is: moving in a straight line at a constant speed, or remaining motionless. If an object does not have a constant velo...
The canoe is changing direction. So, the canoe is accelerating.
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What do these two changes have in common? rust forming on a metal gate burning a candle
[ "Both are chemical changes.", "Both are caused by heating.", "Both are only physical changes.", "Both are caused by cooling." ]
0
closed choice
grade8
natural science
chemistry
Chemical reactions
Compare physical and chemical changes
Matter is made of very small particles called atoms. Atoms can be linked together by chemical bonds. When two or more atoms link together, they form a molecule. In a chemical change, the chemical bonds in the molecules break. The atoms then link together to form different molecules. The types of molecules in matter bef...
Step 1: Think about each change. Rust forming on a metal gate is a chemical change. As the gate rusts, the metal turns into a different type of matter called rust. Rust is reddish-brown and falls apart easily. Burning a candle is a chemical change. Both the wick and the melted wax burn. They react with oxygen in the ai...
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Compare the motion of two fish. Which fish was moving at a lower speed?
[ "a fish that moved 10miles in 10hours", "a fish that moved 30miles in 10hours" ]
0
closed choice
grade2
natural science
physics
Force and motion
Compare the speeds of moving objects
An object's speed tells you how fast the object is moving. Speed depends on both distance and time. Distance tells you how far the object has moved. One unit used to measure distance is the mile. Time tells you how long the object has spent moving. One unit used to measure time is the hour. Think about two objects movi...
Look at the distance each fish moved and the time it took to move that distance. One fish moved 10 miles in 10 hours. The other fish moved 30 miles in 10 hours. Notice that each fish spent the same amount of time moving. The fish that moved 10 miles moved a shorter distance in that time. So, that fish must have moved a...
Will these magnets attract or repel each other?
[ "repel", "attract" ]
0
Two magnets are placed as shown.
closed choice
grade5
natural science
physics
Magnets
Identify magnets that attract or repel
Magnets can pull or push on other magnets without touching them. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes are called magnetic forces. Magnetic forces are strongest at the magnets' poles, or ends. Every magnet has two poles: a north pole (N) and a south pole (...
To predict if these magnets will attract or repel, look at which poles are closest to each other. The north pole of one magnet is closest to the north pole of the other magnet. Like poles repel. So, these magnets will repel each other.
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Is the following statement true or false? A plant cell has a cell membrane.
[ "false", "true" ]
1
true-or false
grade4
natural science
biology
Cells
Cell part functions: true or false
A plant cell has a cell membrane. This statement is true. Every cell has a cell membrane. The cell membrane controls which substances enter and leave the cell.
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What is the volume of a paper drinking cup?
[ "110 liters", "110 milliliters" ]
1
Select the better estimate.
closed choice
grade5
natural science
units-and-measurement
Units and measurement
Choose metric units of volume
Measurements are written with both a number and a unit. The unit comes after the number. The unit shows what the number means. Volume is a measurement of how much space something takes up. There are many different units of volume. When you are using metric units, volume may be written in units of milliliters or liters....
The better estimate for the volume of a paper drinking cup is 110 milliliters. 110 liters is too much.
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Complete the statement. Hydrogen fluoride is ().
[ "a compound", "an elementary substance" ]
0
Hydrogen fluoride is used to make chemicals that can help keep refrigerators cool. The chemical formula for hydrogen fluoride is HF.
closed choice
grade7
natural science
chemistry
Atoms and molecules
Classify elementary substances and compounds using chemical formulas
There are more than 100 different chemical elements, or types of atoms. Chemical elements make up all of the substances around you. A substance may be composed of one chemical element or multiple chemical elements. Substances that are composed of only one chemical element are elementary substances. Substances that are ...
You can tell whether hydrogen fluoride is an elementary substance or a compound by counting the number of atomic symbols in its chemical formula. An atomic symbol consists of either one capital letter or a capital letter followed by one or two lowercase letters. The chemical formula for hydrogen fluoride, HF, contains ...
Is chrysotile a mineral or a rock?
[ "mineral", "rock" ]
0
Chrysotile has the following properties: pure substance found in nature not made by living things translucent fixed crystal structure solid
closed choice
grade8
natural science
earth-science
Rocks and minerals
Identify rocks and minerals
Minerals are the building blocks of rocks. A rock can be made of one or more minerals. Minerals and rocks have the following properties: Property | Mineral | Rock It is a solid. | Yes | Yes It is formed in nature. | Yes | Yes It is not made by organisms. | Yes | Yes It is a pure substance. | Yes | No It has a fixed cry...
Chrysotile has all the properties of a mineral. So, chrysotile is a mineral.
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Based on this information, what is Kitty's genotype for the body hair gene?
[ "bb", "a hairless body" ]
0
In a group of cats, some individuals have a hairy body and others have a hairless body. In this group, the gene for the body hair trait has two alleles. The allele B is for a hairy body, and the allele b is for a hairless body. Kitty, a cat from this group, has a hairless body. Kitty has two alleles for a hairless body...
closed choice
grade8
natural science
biology
Genes to traits
Genetics vocabulary: genotype and phenotype
All organisms have pieces of hereditary material called genes, which are passed from parents to offspring. Genes contain instructions for building the parts of an organism. An organism's genes affect its observable traits, including its appearance, its behavior, and which diseases it may have. Genes may have different ...
An organism's genotype for a gene is its combination of alleles for that gene. Kitty has two alleles for a hairless body (b). So, Kitty's genotype for the body hair gene is bb.
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Select the one animal that has all of the mammal traits listed above.
[ "Adult tiger salamanders have moist, smooth skin with stripes. They live in burrows underground, but they begin their lives in water. Young tiger salamanders hatch from eggs with no shells underwater.", "Okapis have hair and live in forests in Central Africa. Female okapis feed their offspring milk. Adult okapis ...
1
Mammals are a group of animals with similar traits. The following traits can be used to identify mammals: They feed their offspring milk. They have fur or hair. Observe the animals and read the descriptions.
closed choice
grade5
natural science
biology
Classification
Use evidence to classify mammals, birds, fish, reptiles, and amphibians
Scientists sort animals with similar traits into groups. This is called classification. Classification helps scientists learn about how animals live. How do scientists classify animals? First, they make observations about an animal. Scientists observe the animal's traits, including its body parts and behavior. Then, sc...
To decide if an animal is part of a group, look at the traits of the group. Mammals have the following traits: They feed their offspring milk. They have fur or hair. Compare each animal's traits to the group's traits. Select the animal with traits similar to the group's traits. A tiger salamander has the following trai...
What is the expected ratio of offspring with sweet fruit to offspring with sour fruit? Choose the most likely ratio.
[ "1:3", "4:0", "0:4", "3:1", "2:2" ]
0
In a group of muskmelon plants, some individuals have sour fruit and others have sweet fruit. In this group, the gene for the fruit taste trait has two alleles. The allele for sweet fruit (f) is recessive to the allele for sour fruit (F). This Punnett square shows a cross between two muskmelon plants.
closed choice
grade8
natural science
biology
Genes to traits
Use Punnett squares to calculate ratios of offspring types
Offspring phenotypes: dominant or recessive? How do you determine an organism's phenotype for a trait? Look at the combination of alleles in the organism's genotype for the gene that affects that trait. Some alleles have types called dominant and recessive. These two types can cause different versions of the trait to a...
To determine how many boxes in the Punnett square represent offspring with sweet fruit or sour fruit, consider whether each phenotype is the dominant or recessive allele's version of the fruit taste trait. The question tells you that the f allele, which is for sweet fruit, is recessive to the F allele, which is for sou...
What is the capital of Maryland?
[ "Annapolis", "Biloxi", "Albany", "Baltimore" ]
0
closed choice
grade3
social science
geography
State capitals
Identify state capitals of the Northeast
Annapolis is the capital of Maryland.
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Which is a compound sentence?
[ "Malia will change the batteries in the radio tomorrow.", "Jon makes toast for breakfast, or he eats a banana later at school." ]
1
closed choice
grade4
language science
grammar
Sentences, fragments, and run-ons
Is the sentence simple or compound?
A simple sentence is a sentence with only one subject and predicate. The pitcher threw the ball to first base. A compound sentence is two simple sentences joined by a comma and a conjunction such as and, but, or, or so. The pitcher threw the ball, and the batter hit it. Some simple sentences have a compound subject or ...
The second sentence is the compound sentence. It is made up of two simple sentences joined by a comma and the conjunction or. Jon makes toast for breakfast, or he eats a banana later at school.
Which country is highlighted?
[ "Cuba", "Jamaica", "Haiti", "The Bahamas" ]
0
closed choice
grade6
social science
geography
The Americas: geography
Identify and select countries of the Caribbean
This country is Cuba. Does Cuba have any territorial disputes? Cuba claims to own Guantanamo Bay Naval Base, which is a disputed territory. In other words, multiple countries or groups claim that the area rightfully belongs to them. The United States controls the area and uses it as a military base and prison. A treaty...
Which of these states is farthest east?
[ "South Dakota", "Texas", "Illinois", "Georgia" ]
3
closed choice
grade3
social science
geography
Geography
Read a map: cardinal directions
Maps have four cardinal directions, or main directions. Those directions are north, south, east, and west. A compass rose is a set of arrows that point to the cardinal directions. A compass rose usually shows only the first letter of each cardinal direction. The north arrow points to the North Pole. On most maps, north...
To find the answer, look at the compass rose. Look at which way the east arrow is pointing. Georgia is farthest east.
What is the capital of Oregon?
[ "Portland", "Salem", "Cheyenne", "Colorado Springs" ]
1
closed choice
grade4
social science
geography
State capitals
Identify state capitals of the West
Salem is the capital of Oregon.
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Complete the statement. Bromomethane is ().
[ "an elementary substance", "a compound" ]
1
Bromomethane was once used by farmers to kill harmful organisms in soil. It is no longer used because it damages the atmosphere's ozone layer. The chemical formula for bromomethane is CH3Br.
closed choice
grade6
natural science
chemistry
Atoms and molecules
Classify elementary substances and compounds using chemical formulas
There are more than 100 different chemical elements, or types of atoms. Chemical elements make up all of the substances around you. A substance may be composed of one chemical element or multiple chemical elements. Substances that are composed of only one chemical element are elementary substances. Substances that are ...
You can tell whether bromomethane is an elementary substance or a compound by counting the number of atomic symbols in its chemical formula. An atomic symbol consists of either one capital letter or a capital letter followed by one or two lowercase letters. The chemical formula for bromomethane, CH3 Br, contains three ...
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Which is a compound sentence?
[ "You can make a quill pen with a goose feather.", "Colleen forgot to bring her dictionary, so she will borrow mine." ]
1
closed choice
grade4
language science
grammar
Sentences, fragments, and run-ons
Is the sentence simple or compound?
A simple sentence is a sentence with only one subject and predicate. The pitcher threw the ball to first base. A compound sentence is two simple sentences joined by a comma and a conjunction such as and, but, or, or so. The pitcher threw the ball, and the batter hit it. Some simple sentences have a compound subject or ...
The first sentence is the compound sentence. It is made up of two simple sentences joined by a comma and the conjunction so. Colleen forgot to bring her dictionary, so she will borrow mine.
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Which correctly shows the title of a play?
[ "\"Aliens at School\"", "***Aliens at School***" ]
1
closed choice
grade6
language science
punctuation
Formatting
Formatting titles
The title of a book, movie, play, TV show, magazine, or newspaper should be in italics. If you write it by hand, it can be underlined instead. A Midsummer Night's Dream The title of a poem, song, article, or short story should be in quotation marks. "You Are My Sunshine"
A play should be in italics. The correct title is **Aliens at School**.
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Based on this information, what is this scarlet rosemallow plant's genotype for the flower color gene?
[ "white flowers", "ff" ]
1
In a group of scarlet rosemallow plants, some individuals have red flowers and others have white flowers. In this group, the gene for the flower color trait has two alleles. The allele F is for red flowers, and the allele f is for white flowers. A certain scarlet rosemallow plant from this group has white flowers. This...
closed choice
grade8
natural science
biology
Genes to traits
Genetics vocabulary: genotype and phenotype
All organisms have pieces of hereditary material called genes, which are passed from parents to offspring. Genes contain instructions for building the parts of an organism. An organism's genes affect its observable traits, including its appearance, its behavior, and which diseases it may have. Genes may have different ...
An organism's genotype for a gene is its combination of alleles for that gene. The scarlet rosemallow plant has two alleles for white flowers (f). So, the plant's genotype for the flower color gene is ff.
Which statement describes the Steigerwald Forest ecosystem?
[ "It has warm, wet summers and cold, wet winters.", "It has many different types of trees." ]
0
Figure: Steigerwald Forest. The Steigerwald Forest is a temperate deciduous forest ecosystem in Bavaria, a state in southern Germany. This forest has many oak and beech trees.
closed choice
grade8
natural science
biology
Ecosystems
Describe ecosystems
An environment includes all of the biotic, or living, and abiotic, or nonliving, things in an area. An ecosystem is created by the relationships that form among the biotic and abiotic parts of an environment. There are many different types of terrestrial, or land-based, ecosystems. Here are some ways in which terrestri...
A temperate deciduous forest is a type of ecosystem. Temperate deciduous forests have the following features: warm, wet summers and cold, wet winters, soil that is rich in nutrients, and only a few types of trees. So, the following statements describe the Steigerwald Forest ecosystem: warm, wet summers and cold, wet wi...
What is the name of the colony shown?
[ "Delaware", "Wisconsin", "New Jersey", "Massachusetts" ]
0
closed choice
grade8
social science
us-history
Colonial America
Identify the Thirteen Colonies
The colony is Delaware.
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Which of the following contains a vague pronoun reference?
[ "Rick waved goodbye to Dan as his train pulled out of the station.", "As Dan's train pulled out of the station, Rick waved goodbye to him." ]
0
closed choice
grade11
language science
writing-strategies
Pronouns
Identify vague pronoun references
When writing, make sure to avoid vague pronoun references. A vague pronoun reference occurs when a pronoun could refer to more than one possible antecedent. When Lisa and Kim finally landed, she breathed a sigh of relief. The pronoun she could refer to either Lisa or Kim, so the meaning of the sentence is unclear. Vagu...
The first answer choice contains a vague pronoun reference. The pronoun his could refer to Rick or Dan. Rick waved goodbye to Dan as his train pulled out of the station. The second answer choice shows a possible correction for the vague pronoun reference. The text has been rewritten so that the meaning is clear. As Dan...
What can Peter and Bill trade to each get what they want?
[ "Peter can trade his tomatoes for Bill's broccoli.", "Peter can trade his tomatoes for Bill's carrots.", "Bill can trade his broccoli for Peter's oranges.", "Bill can trade his almonds for Peter's tomatoes." ]
0
Trade happens when people agree to exchange goods and services. People give up something to get something else. Sometimes people barter, or directly exchange one good or service for another. Peter and Bill open their lunch boxes in the school cafeteria. Neither Peter nor Bill got everything that they wanted. The table ...
closed choice
grade8
social science
economics
Basic economic principles
Trade and specialization
Look at the table and images. Peter wants broccoli. Bill wants tomatoes. They can trade tomatoes for broccoli to both get what they want. Trading other things would not help both people get more items they want.
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Which is a simple sentence?
[ "Last night we heard an owl outside in the oak tree.", "Marvin can iron this shirt, or he can wear a different one." ]
0
closed choice
grade3
language science
grammar
Sentences, fragments, and run-ons
Is the sentence simple or compound?
A simple sentence is a sentence with only one subject and predicate. The pitcher threw the ball to first base. A compound sentence is two simple sentences joined by a comma and a conjunction such as and, but, or, or so. The pitcher threw the ball, and the batter hit it. Some simple sentences have a compound subject or ...
The second sentence is the simple sentence. It has one subject and predicate. Last night we heard an owl outside in the oak tree.
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Which type of sentence is this? As Colin sat down on the rickety old chair, it abruptly collapsed beneath him.
[ "compound", "complex", "compound-complex", "simple" ]
1
closed choice
grade8
language science
grammar
Phrases and clauses
Is the sentence simple, compound, complex, or compound-complex?
A clause is a group of words that contains both a subject and a predicate. An independent clause is a complete thought that can stand alone as a sentence. A dependent clause (or subordinate clause) is not a complete thought and cannot stand alone as a sentence. the oranges on our tree are ripe The clause can stand alon...
The sentence is complex. It is made up of an independent clause and a dependent clause. The dependent clause begins with the subordinating conjunction as. As Colin sat down on the rickety old chair, it abruptly collapsed beneath him.
Think about the magnetic force between the magnets in each pair. Which of the following statements is true?
[ "The magnitude of the magnetic force is smaller in Pair 2.", "The magnitude of the magnetic force is smaller in Pair 1.", "The magnitude of the magnetic force is the same in both pairs." ]
2
The images below show two pairs of magnets. The magnets in different pairs do not affect each other. All the magnets shown are made of the same material.
closed choice
grade8
natural science
physics
Velocity, acceleration, and forces
Compare magnitudes of magnetic forces
Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes between magnets are called magnetic forces. The strength of a force is called its magnitude. The greater the magnitude of the magnetic force between two magnets,...
Both magnet sizes and distance affect the magnitude of the magnetic force. The sizes of the magnets in Pair 1 are the same as in Pair 2. The distance between the magnets is also the same. So, the magnitude of the magnetic force is the same in both pairs.
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Which text uses the word literally in its traditional sense?
[ "Jen adores the classic Renaissance style of the Rialto Bridge in Venice. She was surprised to learn that the bridge remains functional even though it is literally hundreds of years old.", "Jen adores the classic Renaissance style of the Rialto Bridge in Venice. She was surprised to learn that the bridge remains ...
0
closed choice
grade11
language science
writing-strategies
Word usage and nuance
Explore words with new or contested usages
Words change in meaning when speakers begin using them in new ways. For example, the word peruse once only meant to examine in detail, but it's now also commonly used to mean to look through in a casual manner. When a word changes in meaning, its correct usage is often debated. Although a newer sense of the word may be...
The second text uses literally in its traditional sense: in a factual, non-exaggerated way. Jen adores the classic Renaissance style of the Rialto Bridge in Venice. She was surprised to learn that the bridge remains functional even though it is literally hundreds of years old. The first text uses literally in its nontr...
What is the capital of Oklahoma?
[ "Austin", "Tulsa", "Baton Rouge", "Oklahoma City" ]
3
closed choice
grade4
social science
geography
State capitals
Identify state capitals of the Southeast
Oklahoma City is the capital of Oklahoma.
Think about the magnetic force between the magnets in each pair. Which of the following statements is true?
[ "The magnitude of the magnetic force is greater in Pair 2.", "The magnitude of the magnetic force is the same in both pairs.", "The magnitude of the magnetic force is greater in Pair 1." ]
2
The images below show two pairs of magnets. The magnets in different pairs do not affect each other. All the magnets shown are made of the same material.
closed choice
grade6
natural science
physics
Velocity, acceleration, and forces
Compare magnitudes of magnetic forces
Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes between magnets are called magnetic forces. The strength of a force is called its magnitude. The greater the magnitude of the magnetic force between two magnets,...
The magnets in Pair 2 attract. The magnets in Pair 1 repel. But whether the magnets attract or repel affects only the direction of the magnetic force. It does not affect the magnitude of the magnetic force. Distance affects the magnitude of the magnetic force. When there is a smaller distance between magnets, the magni...