We are having an organised activity party in the local leisure centre for an hour or so and then they go to another room for the birthday tea. Twelve 7 yr old boys. I've got to take it all there, not make it on the premises. Never done this before so how many sandwiches etc? What would be a good mix of stuff? Don't want to have to clear tons of waste into a bin bag. Bit worried that they'll just rampage around and not eat, but on the other hand don't really want to have to think about any more party games etc...