Hi Shana!
FastPass+ reservations will definitely help to ensure that your family will be able to enjoy many of the attractions on your "must-do" list while bypassing their Standby queues. This works especially well when traveling with little ones because it can be really hard for them to wait in long queues for their favorite things. Be sure to download the
Play Disney Parks mobile app for your trip because my kids love to play the app's trivia and games while we are waiting in queues during vacation!
When using the FastPass+ System, all ticketed Guests who will be enjoying the attraction or entertainment experience need to have a FastPass+ reservation. So when you will be using FastPass+ reservations with your little ones, both the adults and the children need to have FastPass+ reservations. Keep in mind that Guests who are under 3 years old receive complimentary admission to Walt Disney World Resort. So since they do not have theme park tickets, you will not need FastPass+ reservations for any of your little ones who are 2 years old and under. They definitely won't miss out on any of the fun, though, because they can enter the FastPass+ queue with the rest of the family when they redeem their FastPass+ reservations.
When my family makes FastPass+ reservations, we like to let everyone pick something they would enjoy during the day. Since you have three little ones, you could let each of your kids select one FastPass+ reservation per day and everyone can enjoy all of these attractions together as a family. This will help make sure that your itinerary includes something on each child's "must-do" list every day!
Feel free to come back and see us with additional questions as you continue planning your trip. T-T-F-N, ta ta for now!
~Crystal