I need to design a concentration exercise program for a 9 year old client. Any suggestions?

In addition at 9 years old he needs to enjoy what he is doing. SO make it fun. He shouldn't be thinking of this as his exercise time but a fun time where he plays lots of games. Some suggestions from the IYCA on training kids this age:
- Multi-directional and multi-planer movements
-Run, crawl, skip, jump, climb, etc
- Keep it FUN

I can't agree more than with Scot's encouragement to make your sessions with him a fun time. Make it a game time, not a workout time.

I might also add that the decision regarding medications is one to be made between the father and the child's physician. I also suggest that you consult with the child's physician to make sure that your activity plan (not an exercise plan, even though it is exercise) is appropriate and consistent with the child's medical history.

I also emphasize Philip's brief comment about no weights. The epiphysis of the long bones aren't closed and weight added to body weight can put them at risk.

Have fun!