4 + 3 = 8?Whoops! That’s not right.Looks like a job for the eraserheads!The three eraserheads—an owl, a crocodile, and a pig—live atop three pencils in the land of paper, rulers, letters, and numbers. Their job is to help a little boy correct his mistakes. But one day they make a mistake of their own—and what happens next is something nobody expected.