I was in a classroom a few years ago and the student was like the ball in a pinball machine! He was up and moving during my entire observation. There were moments where he could be cajoled into sitting and attending to a task, but they were few (very few), far between, and super short. The teacher looked at me needing help. Her job had become an exhausting workout.
I left and came back the next day with a few ideas and some fidget toys. Guess what… it helped.