When we went on our cruise last year, my daughter grabbed a whole bunch of the luggage tags for separating the luggage when leaving the ship.
They had different characters and rubber band.
I also got stickers from a really nice security guard at the Boardwalk entrance to Epcot. When I told him about my daughter's class, he told me to hold on, he walked into a room and came out with about 50 stickers.
They were little security type badge stickers.
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Just an FYI, I don't think any of her classmates thought that she was bragging about her trip, instead I think they were appreciative that they were thought of and missed while she was away.