V-brakes. But if the group are all using the same bikes (as often happens if they’re supplied by the centre) then a set of disc pads won’t go astray.
My first day of tutoring was with a group of 8-11 yr olds. Snow started to fall when we were 30 mins from the minibus. So, we turned round and headed back. Both leaders were frozen by the time we got to the bus and one of the kids was in tears he was so cold. So, we had our sandwiches and warmed up. As snow was lying on the ground we couldn’t go back out – because the insurance wouldn’t cover us, so we drove back to the base. One of the kids wet himself, and another kid had a knife so we had to stop and confiscate that. Then we spent 3hrs in the pouring rain doing skills sessions in the playground – the kids were warm as they were cycling around and around, while we had to stand and just put the obstacles back together. I was frozen solid by the end of the day.
And some of the kids even said "thank you" when they went home.
Wrap up warm!
Have also had groups where some spoke no English and hadn’t even ridden a bike before.
Always a good laugh though :-)