Hi Nyssa!
Wow! That's a tough choice! The good news is that you really can't go wrong with any time you choose. Walt Disney World is always a perfect vacation choice!
Personally, I would choose the week leading up to Labor Day in a
cabin at Disney's Fort Wilderness Resort. I love the weather, lower crowd levels and events during late August/early September. Generally, when most U.S. schools are in session, you'll find lower crowd levels at Walt Disney World Resort. Since many schools, especially in the South, head back to school in mid-August, you'll notice smaller crowds at the theme parks and resort. Park hours may be shorter at this time of year, but this is offset by the lower crowds. You'll be able to accomplish just as much in a little less park time.
The weather in early September is generally great too. Daytime will still be hot enough for pool and water time, but the evenings do cool off a bit from the heat of the summer. Perfect!
Another deciding factor is the choice of a Fort Wilderness Cabin over tent camping. While I love to camp, I think you'll really enjoy the cabin amenities after a fun day at the park. The small kitchen will be a great place for a quick breakfast on the go, or a nice spot to grab a few snacks. You can even pre-order groceries and have then delivered right to your cabin. That's a great bonus with kids! An added plus is the full bathroom as well. Super convenient! And, once the kids are in bed for the night, you can relax on your own private patio.
During late August, Walt Disney World will also be hosting some fun events like
Mickey's Not-So-Scary Halloween Party at the Magic Kingdom and the
Epcot International Food & Wine Festival. Even if you decide not to attend these events, you'll be able to enjoy the Fall decorations and extra touches sprinkled throughout the parks. I love the Autumn touches on Main Street, U.S.A. in the Magic Kingdom. They lend an extra magical touch to a wonderful place!
I hope this helps you pick the perfect time for your family vacation! Please don't hesitate to reach out again if the Disney Parks Moms Panel can help with additional planning details!
Kathie