They can be decorated to use as miniature vases for a bouquet of artifcial flowers. Use several of various sizes and decorate with different masks to build a totem pole. Use 2 large spools with a long strip of paper to write and illustrate a story(paper film strip).
Wooden spools are awesome to use in crafts. Perhaps you could stack them together with glue and make a Christmas tree-shaped ornament, fasten them into a zipper pull, or more traditionally thread them and make jewelry.
The most common craft that is wooden spools are used are little wooden people. Easy to make and easy to paint. Legs and arms can be attached. The head and the body are the actual wooden spool. You can add eyes and desired faces.