How do Shrinky-Dinks work?

If you grew up in the 1970s or 1980s, chances are you remember having fun with magical little bits of plastic. So how do Shrinky-Dinks work?

How to tell if gold is real

It only makes sense that you would want to find out if the jewelry your aunt left you is worth anything, so here's how to tell if gold is real or fake.