Albeham,
I was a scout leader for 10 yrs, lots of summer camps etc. Each scout is supposed to have their own 1st aid kit. It will cover the general scrapes, scratches, burns, bites and blisters. Before we went to a summer camp I reviewed the medical history of each kid to see if there were any special issues, i.e. diabetes, allergies, med requirements etc. If there were I would get with the kids parents and make sure the kid had what they needed i.e. epi pens, insulin etc. If they were on chronic meds like ADD meds, they have to be kept at the base aid station and dispensed from there. The troop/I had my own personal aid bag but still most of that was for the general maladies. Dispensing even over the counter meds is controversial so be careful there. I'm a PA and it was acceptable for me to give OTC meds with parental consent. If you encounter something outside the realm of your aid kit get the kid to the aid station. In my experience they usually had an EMT type there and or a nurse, both of which were more than capable of triaging a pt. If they need to, they can activate the EMS.
Have fun and don't worry too much. A friend of mine once told me, "A kid can take a fall that would kill a horse, so relax."