We tested out Shrinky Dinks: Bake & Shape 3D Jewelry (Alex), and it is a fun thing to do when you are bored. It is also a fun and easy jewelry maker.
You can make rings, earrings, and bracelets. In the box it comes with a bracelet and ring maker. You can make two sets of earrings. They recommend a toaster.
The jewelry may not come out symmetrical. Read the directions carefully because the Shrinky Dinks have to be baked at different temperatures.