The ferry is also just a nice ride. A nice wind down between the park and dinner. With your little "team" the chill time might have some value! We took the ferry to GF, but after dinner hopped the monorail back to MK to get a resort bus.
WDW has something FREE: each transportation mode has a card, so your kids can get one from the Ferry, another from the monorail and one from the bus drivers. It was actually our ferry driver that gave us the first card and explained what they are, how cool!