What you can do is teach him some solid organizational skills. My son is expected to fill out a school planner each day and to get each teacher to sign it so that we know what he has written down is accurate. If he doesn't get it signed, no computer that night. We also worked out a good binder/folder system so he can keep track of his work and notes. It takes a committment to be VERY consistent in checking planners, helping him organize his backpack (his school doesn't use lockers so this is really important). All that still would not be workable without meds for him, but he is learning some basic strategies that he's going to have to use for the rest of his life. ADHD isn't going to go away once he's out of school, so a combination of medication and behavioral techniques is a must.