Price: $9.99 on Steam (though they often have sales–put it in on your wishlist and they’ll notify you when it goes on sale)
Grade Levels: Ages to 5 to however old you are
Content Area: Science, Math, Astronomy
What Is It? Technically this isn’t a game, but an actual simulation of the universe. There are no goals, and the only rules are physics. Have fun.
Game-Based Learning Apps: Universe Sandbox