re: Wristwatch recommendations for a 13yr old boy

If you are trying to foster his iterest in watches, I would go with some iteration of the Casio MDV106. It's analog, 200 M water resistance and quartz, so can be beat up without affecting performance. One variant of it is pictured above. I think that is a perfect intro and if watches aren't his bag as a hobby, he still has a useful item that will last a good long time.