On one hand it would explain to him why he has difficultly with his literacy and why he sees the SEN teacher once a week (alto he doesn't know that's her title but he does know that he's getting extra help and sometimes claims it's because he's stupid :(
However, I fear it might label him too early and also that he may use it as an excuse to give up! My father always told us we'd never be good at maths and as I result, I stopped trying and although I agree I doubt I'd ever have become a mathematician, I think I could have done better if I'd tried harder.
Parents of dyslexic kids of a similar age: do your children know? Your views on this matter would be greatly received