Goodbye schoolbooks and teachers, hello ice cream and sand. Summer is here, and parents may be looking for ways to keep their children occupied during the hot summer days. It's time to get your children off the couch and into the sun. Check out these environmentally friendly toys that will teach your children about BEing green while keeping them out of your hair. X7 Fuel Cell Car Ready, set, zoom off with the X7 Fuel Cell Car this summer. Made by Thames & Kosmos, this water-powered vehicle will teach kids about alternative energy sources while they build the fuel cell car piece by piece. Fill the tank with water and watch the wonder of science as the hydrogen and oxygen separate to make this car run. Ages: 10+ Retailer: FatBrainToys.com $87.95 Dyna Flyer Learn about aerodynamics and the use of wind power with the Dyna Flyer by Elite Fleet. Great for the park, yard, or beach, kids can crank the plane's launcher and watch it take off for up to 30 seconds. And the best part? This battery-less operated toy means one less item on your "to buy†list. Ages: 8+ Retailer: GrowingTreeToys.com $24.99 Sand Play Set No sand is undiggable or castle un-buildable with this four piece environmentally friendly sand play set by Green Toys Inc. Made from recycled plastic milk containers that reduce landfill waste and lower CO2 emissions, this set is sure to leave an undetectable carbon footprint. Ages: 3+ Retailer: Amazon.com $15.42 Tree House Play Set Create a jungle adventure with this towering wooden play set by Melissa and Doug. Complete with a foliage canopy, pulley system, retractable stairs, a working trap door, porch swing, hammock, tire swing and wooden play figures, it's a fitting outdoor tree house for the 3 and over crowd. Given wood's durability over plastic, you're likely to pass this toy down to future generations than send it off to a landfill. Ages: 3+ Retailer: CowandLizard.com $99.99 Eco-Truck Loader The Eco-truck loader by Sprig Toys is a new take on a classic toy. Made from reclaimed wood and recycled plastic composites, this truck also uses minimized packaged from recycled paper and board. Ages: 3+ Retailer: SprigToys.com $14.99 The Power House Kit Waken your child's inner architect with the Power House Kit from Gaiam. The kid-built house comes with solar panels, a wind turbine and greenhouse. What makes this house even more entertaining is the storyline included with the instructions. Watch your child's creativity soar as the goal of the house is to use the limited resources available on this remote island to survive. Your life depends on your ability to harness the renewable powers of nature, according to Gaiam. Forget The Sims, you can create your own world with the Power House Kit. Ages: 12+ Retailer: Gaiam.com $175