Appropriate section for my son in his next tournament?



I was never blessed with a child. However, I can relate to when I was your son's age. Why don't you ask him, if he would rather play harder opponents.
Also I agree winning feels good, and helps build excitement in the young. You also know your son. However you can always go back to a lower level. He may actually get excited over a possible harder challange also, so I would listen to what he said, after all it affects, or will affect him, one way or another. Sometimes parents can be to pushy, I am not saying you are by any means. Keep in mind what is best for him, and his thoughts on the matter. I hope this helps.
He's starting 1st grade. Chesskid fast rating 1,020; chess.com rating for 15 | 10 games is 1150 (only played 15 games on chess.com though). He did an U600 tournament last weekend and won all his games.
Should we put him in the next tourney at U600, or 600 - 1000?
Thanks in advance!