Metal that melts in your palm? Check.
Fruit extract that makes Tobasco taste like glazed donuts? Check.
Purple frikkin' Lasers?!? Check.
One of our best Nature Directors at summer camp was actually science major (she now has her Doctorate and lectures around the world on epidemiology). She ran a very creative program and she spent a bit of her budget on cool science education toys. The kids loved her program.
If you would like to add a little zip to teaching science at camp you should check out this cool article: 11 Cheap Gifts Guaranteed To Impress Science Geeks