Hi there, Renata!
Disney's All-Star Movies Resort does offer a variety of kid-friendly activities that are sure to delight.
Because you are visiting in August, my first recommendation for you would be a dip in one of the pools! You'll find fun, friendly Cast Members engaging the children in pool games most afternoons (weather permitting). Make sure to get a schedule of events (a Recreation Flyer) when you check in.
There is a shaded playground on the grounds, as well as an arcade (the arcade will, of course, require additional payment).
Most of the Value Resorts will offer comparable activities, centered largely around the pool. Not all of the action will take place in the water, mind you; there have been Big Wheel races, bingo games, and more, but all done poolside -- it's a central location for that kind of fun.
Again, pick up a schedule when you arrive. That will fill you in on all of the excitement for the day, and allow you to plan your activities.
Have a wonderful time!
See you later, celebrator,
-Deborah B.