Several of my students have been giving my puppet, M. le Bec, their spare Silly Bandz---for those who have not seen this fad, it's plastic elastic band-like bracelets which look like a bracelet while you are wearing it, but take on a shape when you take them off. The kids collect and trade them.
At first it was just a funny joke in my Grade 2 class, but to my surprise it has actually evolved into a real curriculum moment. He has too many to wear now, so he has been keeping them inside his hat. Every day we take five minutes and lay them out, and he gets to choose one to wear for the day. So we go through them all: tu veux le chat? tu veux le chien? etc.
The kids (even the JK kids!) are at the point, after a week, where if I don't say the word right away, they jump in with the correct word themselves. They are learning a ton of vocabulary for things that might not come up in another context. And the collection is ever-changing---my niece is into the Silly Bandz thing too and has volunteered some of her collection for the cause, and kids are still offering them to me because they get a kick out of seeing him in the bracelets.