When my kids were babies, I made up some of the pentagon balls using my Grandmother's stash of polyester scraps. It worked out fabulous!! If you can imagine all the bright colors and funky patterns. It made a really cute ball. I put some jingle bells inside to make them jingle when the kids played with them.
So I got thinking about my felted sweaters and thought they would sew up nicely into a ball. Sure enough, it worked out great.
I don't have any little ones around my house anymore, but my border collie loves them, and I am sure cats would get a kick out them too.
This is a simple fun project for even the beginner seamstress.