Maybe the teachers could try being more direct with your son? Like in the case of the shape hunting and drawing. If they had just let him know that they wanted to see if he could draw shapes that he had seen, he probably would have done it.

When my dd was that age I remember that the first thing I had to do when picking her up from school was to hand her some protein. Then I could ask her about her day in 5 or 10 minutes.