I saw this idea at the Iowa Children's Museum last summer and never got around to making them. Last week Sweet P found the baggy of facial features and asked what it was. I said, "Let's find out!" and quickly glued magnets to the back of the features. Making faces is one of Sweet P's FAVORITE things to do. She'll make them our of anything. Spots on the wall, food, bubbles, leaves, toys, if you've got 4 things in your hands- she'll make a face for you. I think sometimes she sees what might classify as a "Scary" face in spots on the wall as well (imagination is at work) so we talk about how those spots aren't "real" faces and her imagination is making them, but that's a post for another time!
UPDATE: I laminated these and reglued the magnets and they are much easier to work with! We'll be taking these on our roadtrip in a few weeks, they'll be a great car activity! I've also added mustaches, glasses and more features.