Yesterday I mentioned Steven Caney’s Toy Book as a great source of ideas for homemade kids’ toys. Along the same vein, but with an added bonus, is The Science Explorer by Pat Murphy, Ellen Klages, and Linda Shore of the San Francisco Exploratorium Museum. It’s chock-full of quick, craft-like projects aimed at six- to nine-year-olds, plus explanations of the science behind them. Children a little younger might still be amused by many of the gooey, noisy, flying things, without quite as much technical information, and those a little older might work some into a larger science-fair project. 
Many of the ideas in the book are also available on the Science Explorer Web site.
An added bonus for both book and site? Either this grown-up character featured throughout is a lesbian mom, or my gaydar is seriously off.
Oh no, your gaydar is RIGHT ON with that one, girl!