Had parents' evening on Monday for my DS who is in y5. Came out feeling amazing, told he was very bright, lovely child, doing really well etc. Lacked confidence in maths, but not ability. Son comes home today very upset as he has been moved down a group in maths. I'm not questioning the teachers judgement about this, but surely I could have been told on Monday? I feel that I want to discuss this with her but what's the best way to go about it without it sounding like sour grapes?