Wouldn't it be great if you had a full-time sales force recruiting campers for you? You already have one: Your counselors and former counselors. They're already representatives of your camp, so why not pay them $5 for every camper they send your way?
Five bucks is nothing compared to how much you'd spend to get a new camper anyway. But $5 for a college student is HUGE when they're wondering where their next meal's coming from.
So get in touch with all the camp counselors who worked for you last summer. Call them on the phone or send them an email to let them know they can make $5 or more the easy way. And don't put a cap on how much you'll pay them; if they send you 5 new campers, give them $25 (and so one).
Presto, you've got an instant sales force working for you right now.