I am a first grade teacher on the Ft. Peck Indian Reservation in Montana. I average about 4-5 ADD or ADHD students in my class each year. I've been teaching for 7 years. Here are some strategies that I have found helpful...

1. Get the counselors, parents, etc. involved right away and document everything.
2. When you are on the floor, put a piece of tape in an X or a box for him to stay in. Explain that this is his space and nobody can go in except him.
3. Keep him close to you. I would keep him at arms distance so you can keep a gentle hand on his shoulder, desk, etc.
4. Many "busy" kids need something to touch while you teach to keep their focus. I put a piece of sticky velcro (the soft side) on the underside of their desk. They can rub this velcro while you teach and it helps with their impulse to move about.
5. Walking Papers. We give the student a 2 pocket folder and have him hold onto the left and right side while we trace his hands with a black marker. This shows him exactly where his hands should be when he holds the folder. He takes this folder with him any time he walks in the hallway, to reading, to the OT, bathroom, counselors office, lunch, etc. This folder keeps his hands busy so that he is not using them to hurt or bother someone else. It has worked really well with a boy I have in my class right now. We give him a sticker each day when he has used it well and not forgotten.
6. I've used a sticky note cut into three, four or five strips on their desks. (We target one behavior you want changed at a time.) Each time I have to remind them to sit still (or whatever the behavior is), I take away a strip. If there are any strips left at the end of the day (or half a day) he gets a sticker, computer time, to read a book (whatever he likes).
7. I have let students stand who really have a tough time sitting while they work.