If there's a problem in school, there's no substitute for the world-saving substitute teachers of the S.O.S.! This is the fourth book of this hilarious, highly illustrated early chapter book series. It's Spring Break! Milton Worthy and his family are off on a vacation to Super Fun World. It's a week filled with roller coasters, rides, and fried food--and no super-sub missions for seven whole days. Everything is going according to plan until Milton...