We've been at WDW twice during Pop Warner week. We barely noticed them in the parks. I believe MGM closed at 6 PM that Friday for their exclusive use. Otherwise, we saw them just a few times in the parks and only in very small groups. The people who were the most negatively impacted seemed to be those who were staying at the same resort as the kids. At least some of those folks reported problems with the kids taking over the food courts and pools and being generally unruly and noisy. However, not everyone had that experience, and, as they say, your mileage will vary. I think that, as long as you stay at a resort where they are not staying, you won't have any problems at all.