I went whole hog. I bought moustaches for everyone to wear. I bought her a moustache cookie cutter and moustache paper from Paper Source to use for our craft day, which I put in a bag that I added a paper moustache to.
The fascination that girls this age have with moustaches is perplexing to say the least. (Don't think it's a trend? Search "moustache" on amazon. Moustache mood ring? Hot pink socks with little moustaches?) But she's a teenager now, I guess we aren't supposed to understand!