Brad I buddy boxed a 15 year old that was deaf. I had it easier than you though. His dad could hear and of course sign. So the dad stood next to him and would help move his thumbs and once in while converse in sign to help. I was basicly the plane saver more than the teacher. I should mention the dad had flown in the past. I had it much easier than you. It sounds to me like you guys have come up with a great solution. You may still hit an occasional snag. I would suggest a note pad and pencil be at hand.

David