This is one of my favorite projects. It’s fun, cheap, hands on, and educational. My brothers taught me how to make them when I was about nine years old, but I suspect it originally dates to a time when young boys carried everything they needed in their pockets: Matches, a bit of wire, and a foil gum wrapper. Over time bits of wire gave way to paper clips and pins, and gum apparently doesn’t come in foil wrappers any more, so we’ll make do with regular aluminum foil. Here’s the full how-to with a about two dozen rocket launches included because I was having too much fun.