Our beloved blue fur ball from the around the corner on Sesame Street, Cookie Monster, has become somewhat of a YouTube sensation lately. And his most recent outing on the ubiquitous video site is, ...

Learn about household objects that sink and float in this easy-to-prepare activity. Learn about household objects that sink and float in this easy-to-prepare activity.

What: Earlier this summer we learned about density. Density is the amount of mass in a given volume, or amount of space. Mass is dependent on the number of molecules in an object. Objects that are ...

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