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Unit 2: The Earth-sun-moon system

400 possible mastery points

About this unit

In this unit, you'll explore the inner workings of the Earth-sun-moon system. Discover the secrets of our seasons, learn why the moon waxes and wanes, and find out what causes the stunning spectacle of a solar eclipse.

Why is it summer in Chile when it's winter in the US?


Can't see the moon at night? Don't worry, it's just a phase.
Level up on the above skills and collect up to 240 Mastery points
Put down your sunscreen—it's a total solar eclipse!
Make science come alive in your classroom with free hands-on investigative activities aligned to middle school NGSS standards.
Up next for you:

Unit test

Level up on all the skills in this unit and collect up to 400 Mastery points!