I am looking for an momento for year 2 children moving on to junior school?

Hi - my son is leaving infant school and I was wondering what would be a good momento for the kids to buy to commemorate their time in the school? Previous years, they have had a hooded sweatshirt which looks like their infant school jumper, which is a bit lame when you're going on to a bigger school. The photo idea is out so any suggestions please? There's about 45 kids in total and it would be nice if there was a fundraising element to it if possible (even just �1 per item). Help!