A cocoon is like a cozy sleeping bag made by many moths. When a caterpillar is fully grown, it finds
[823호]
A healthy bedtime routine helps your body and brain recharge. Start by avoiding caffeine after lunch
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Superfoods are foods considered especially healthy because they are packed with nutrients such as fi
[821호]
Submarines can move up and down underwater by changing their density. They take in water through spe
[820호]
A tsunami is a series of powerful waves caused when something suddenly moves a large amount of water
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Vitamins are your body’s helpers behind the scenes. They help everything run smoothly. Vitamin A i
[818호]
How does a place get included on the UNESCO World Heritage List? First, it must meet at least one of
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Before calculators existed, NASA engineers and astronauts used a tool called a slide rule to solve p
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Our lifestyles affect the environment. What we buy, what we eat, and how we get rid of trash can sav
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Radiation is the energy that travels through space or objects. We see it every day. It is the sunlig
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