Sunscreen and stamps are a must, and granola bars are always appreciated. But when it comes to packing up their kids for camp, many parents are leaving the prescription drugs at home. For the 2.5 million kids medicated for attention deficit hyperactivity disorder (ADHD), physicians recommend an occasional break from the meds. The freewheeling days of summer are in some ways the perfect time. But when sleepaway camp is in the cards, drug holidays can present a problem—not just to the counselors having to handle kids who can be off-the-wall, but often also to the campers themselves.