Put on your thinking cap because Discover magazine and Instructables have a task for you. The two are collaborating on the Green Science Fair For a Better Planet, where anyone and everyone can present their unique green ideas and possibly win some prizes in the process.

Discover and Instructables have left the entry criteria wide open: participants can build eco-friendly projects, test and compare earth-friendly products, find new uses for old parts or simply demonstrate effective ways to lead a more environmentally-conscious life.

To find inspiration, you can check out some past Instructables projects such as building your own solar power system, a DIY composter, or constructing an evaporative terra cotta beer chiller to cool your summer drinks without wasting energy.

Among some of the prizes up for grabs are the Celestron Skyscout, a GPS device that will show you the solar system, as well as an MP3 player, a portable wind-up radio or a rockin' Discover magazine t-shirt.

Hit the jump to learn more about the Green Science Fair and get inventing!

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