Why is the sky blue? Weather science
Blue sky with cirrus clouds This is an easy question to ask but the answer is pretty hard. The light that comes from the Sun to Earth looks white, but really it is made [...]
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08, 2017
19
08, 2017
What’s the atmosphere? Weather science
Earth's atmosphere: Did the Earth look like this right after it cooled down? What is the atmosphere? The atmosphere is the air that is wrapped all around a planet. Read more [...]
8
06, 2017
Sharecroppers and cotton – American History
Sharecroppers and cotton: Cotton pickers in the 1800s AD Slavery and the cotton gin The invention of the cotton gin in 1793 AD made it possible for enslaved people to [...]
2
06, 2017
What is nitrogen? Atoms, Elements, Chemistry
Diagram of a nitrogen atom Inside a red giant star, the star smashes lighter atoms together. Smashing atoms gets the star energy to burn, and also leaves extra heavier atoms. Nitrogen [...]
1
06, 2017
Plant food – a nitrogen project – Chemistry
A jug of nitrogen fertilizer It's pretty easy to see just how much a plant needs nitrogen to grow. Just take any two plants (they could be small house plants, [...]
1
06, 2017
Helium balloon projects – Chemistry
You can see that helium is lighter than air by getting a helium balloon. When you let go of it, it goes up, because the helium is lighter than the nitrogen and [...]
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05, 2017
Photosynthesis project – Plants and sunshine – Science Activities
Will your shadow keep the grass from growing? You can see for yourself how important sunlight is to plants. Take any patch of green grass, and cover some of the [...]
