I am a veteran teacher who has just been diagnosed with ADD. I am having a better understanding of just how confusing it can be. Imagine you had fifteen people who all wanted to say something to you, as well as a song in your head. Now imagine that you cannot differentiate between whose voice is which; you cannot filter out thoughts; and you have just eaten a big bag of M&Ms. It is a Frightening and confusing feeling. (Led to a mental health breakdown with me.) While meds can help, as you can see with this boy, they wear off, often at bad times. Here are some things that I do to get me and my ADHD students through a day...

1. Allow student to shift in his seat, change seats, or move around every now and then.
2. Provide quiet "fidget toys". This is crucial during times when you want him to take in a lot of info at once. The thing about this disorder is that it doubles a person's processing time. It comes across as the kid not paying attention, being disruptive, or rude. (We get very defensive when confused.) It does help, for whatever reason, to have something in the hands to fidget with or even (I know this is an unpopular one...) a piece of gum. By occupying the physical impulses, the brain works better and can concentrate.
3. Written plans, goals, and contracts work well. A visual reminder can really make all of the difference in the world.
4. Give the child important jobs to do, especially ones in which he has to do something physical. "Joe, could you bring this to the office for me?" It is crucial that a kid with this disorder feels a part of things. Also, when confused, a lot of ADHD kids will get angry or violent. A pre-arranged signal between you and him could remind him that he is "floating out", and if necessary, signal that he needs to take a short walk to the bathroom or water fountain to cool down.