How old is he?
My son started playing for the 1st grade team this year. I coach and my life pretty much revolves around football but I wasn't going to push my son into it. I thought he was too young (I started organized football in the 5th grade, earliest you could start in my city at the time, after years of dominating the playground scene), but his tee-ball coach was the HC and, after my son said he wanted to play, the coach convinced me it was a good idea, and then asked me to coach after I made the decision to let him play.
It's a lot of fun. I've heard a lot of people say as a parent you enjoy watching your kids more than you enjoyed playing. I'm not there yet, but I can see how that will be the case as he gets older, especially if I continue to coach his team(s).
On another note, my son plays in a AYF league and they don't keep score until the 4th grade. This ticks me off so much. It's not that I care whether we win or lose, but it's an important part of life that should be taught. One day I asked the kids why they were playing football. About half of them said they wanted to win a championship and during every game we've had this year they've asked me if we were winning (during the game) or if we won (end of the game). I'm not going to lie to them. We're 3-0, not that anyone is counting