My son told me that he hated PE. Wasn't solved until crazy patterned curtains in the hall were removed - and 'demonstrating routines' at the end of the lesson did not mean that he needed to touch anyone else or be touched by them. He thought that PE meant that children would be touching him, whatever the activity. Also PE t-shirt still had a label in it (oops!)
PE in the hall? Bare feet on a dusty/gritty floor? How much does your hall echo?
Same space that you use for assembly; but with different rules attached to it for PE lessons?
What does the child think about the lessons? - 'dance is just for girls'?
Motivation? Does he think there is a reason for him to learn those things he doesn't like?
It must be very stressful having a school day packed with things you don't want to do! How often does he get to do what he does like?
Does he lose his 1-1 support during the activities which make him feel bad?
Have you asked his parents for suggestions? They've hopefully got a good feel for when he is making excuses or is truly feeling unwell because of the stress of coping.
Hope my random thoughts help!
