anglagadapee - It is hilarious to know your preteen boy has a good fashion sense. I am not going to say this is not the right age because he can definitely carry any of these haircuts or styles with few modifications. Hereof, you can consider this guide https://beardoholic.com/long-haircuts-boys/ and explore several shaggy and straight-layer haircuts with bangs.

Withal, I can't say how manageable they would be for you or your son. Although I don't suggest long hair for summer but if your boy wants then you should adopt shoulder-length hair or even go with a small bun option for outdoor activities. Probably, your son will become a fashion model in future :D