We've been at WDW during Pop Warner time. Those who had the worst experiences seemed to be those who stayed at the same resorts as the kids. If you stay elsewhere, as we did, you'll probably barely know they are there. They don't spend a whole lot of time in the parks anyway, and when they do then tended to be in small, fairly quiet groups. I know a few people said they ran into large, loud groups of them in the parks, but I think those encounters were probably the exception. Personally, I wouldn't change the dates of my trip over it - I'd just be sure I stayed somewhere else.