Hi Abby,
My first thought for you, especially with the ages of your children, is to visit Disney's Fort Wilderness Resort and attend the
Chip 'n' Dale's Campfire Sing-A-long. You'll simply travel by boat from Magic Kingdom to Fort Wilderness for a very low key, family oriented experience with singing, dancing, photo opportunities, autographs, s'mores and more.
If staying at a Disney Resort Hotel, be sure to check out the weekly activities at your front desk. Movies Under the Stars is a wonderful way to unwind from a busy Park day. Check out the independent site buildabettermousetrip.com for their compiled list of movies and locations.
Visit Disney's Boardwalk for nighttime entertainment in a Coney Island-style backdrop. My kids love the streetmosphere offered here and my husband and I find it lovely to walk the perimeter of Crescent Lake. It's peaceful, yet plenty entertaining for the little ones.
I hope my suggestions were helpful, Abby, and thank you so much for your question! If still in need of more ideas, please don't hesitate to write us back.
Happy planning!
Sherri