Come on Larry, non-structural? Gotta teach the little ones the correct techniques. CherryMax's all the way (one rivet will cost as much as the kit, tho...) ;-)
Absolutely, pulled rivets will work great here, either countersunk (with dimpling) or regular...even Hardware Store ones ...
In all seriousness, though, it's a good test of strength and dexterity using standard rivets. I find the little ones have trouble controlling the gun and bar together; their hand are small and arm strength is low. Even if they concentrate on a single end of the rivet, they still can struggle. My teenage daughters do a good job, but not perfect. When the 20+ somethings come by to help, even the noobs, the firm hand is instantly noticeable and quality improves significantly.
Give the kids a chance on the real deal, then pull out the poppers to get the job done.
I always keep a toolbox kit around as a teaching aid and a lovely parting gift for my riveting partners; it's a great souvenir.