
How do we know about ice ages? Scientists study ice. Scientists study clues from glaciers. Scientists study fossils.
What Do You Think? How did humans live during the ice age?
Photo Credit: Corbin17/Alamy Stock Photo
The Sun/Moon pattern repeats every day. When the Sun comes … read more
They all flash again. These fireflies are called synchronous fireflies. They … read more
Martin is remembered as a hero. He gave a famous … read more
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