Reviewed for 2008, First Grade

From sliding down sewers to watching what happens when a toilet flushes green dye, to riding a roller coaster for over an hour in order to understand the physics behind loop-de-loops, this fantastic DVD series culls the best episodes from Discovery Channel's now defunct television series. Each DVD contains 90 minutes of jam-packed action for kids who thrive on the "why" behind how things work. Whether it's tracking garbage through its journey from street bin to recycling plant, or bumming a ride with an emergency medical crew, kid hosts Jay and Elisha manage to squeeze in an amazing amount of on-the-fly learning, in between all the kid-pleasing talk of slime, roaches, and killer sharks. ($49.99)

Where to buy Popular Mechanics for Kids 6-DVD Boxed Set