Wired Science from KCET PBS has a great story about the old-school chemistry set. Liability, and presumably some common sense, has removed from the toy store shelves such oxymoronic projects as "preparing a safe explosive". This story shows some of those old sets, and demonstrates the interesting and exciting world of chemistry that is available in a safe and controlled environment. Yet another reason to incorporate science into informal learning - it can be fun, but it may also need to be supervised.
Get more Wired Science at their website - I could really post dozens of their stories here. They are great!