I need help! When should I tell him? What should I say? =P?

Don't rush into telling him you don't want to scare him away or anything. My advice to you is to try and hang out with him a little bit so you two can get comfortable with each other and move from in between friends and acquaintances to friends. Then when you are more comfortable it will be easier to tell him. If y'all start hanging out you two will probably have a lot more fun at summer camp too.