1. Label everything.
It's easy to lose things at camp, but if you want it back, it's got to have your name on it.  Label everything from your t-shirts to your tennis racket to your toothbrush.  Use a permanent marker to label socks right on the toe.

Nearly all kids miss something about home when they're away at camp.  It's normal.  If there's something about home you miss, that means there's something about home you love, and that's a wonderful thing.