I just found the coolest website called Dad Can Do. Chris Barnardo's concept is to share projects that Dads can do with their kids, but these are great project ideas for after-school groups and summer camps too.He has ideas for making trains, drawing dragons, decorating boxes to be telephone booths, Batman's spotlight, a floating submarine, glue gun bugs, shadow box frames, and so many more cool things!
If you like the site, check out his book too.