It turns out that some children's books are too controversial to make it on the shelves at a school book fair. 

That's what is happening this week in Monroe, Michigan, where Dav Pilkey's popular Captain Underpants books are for sale—but not the latest installment in the series, Captain Underpants and the Sensational Saga of Sir Stinks-A-Lot.

Why not? One of the main characters sees into the future and find out that he's gay. This revelation is not, as one article noted, "the primary plot line." 

According to Monroe Superintendent Dr. Barry Martin, the word came directly from Scholastic, who "notified us and the school that there was a book that may be a little controversial." That led the parent group in charge of the book fair to decide not to carry Sensational Saga. As they see it, the book fair is where kids shop without parental supervision, and the book could make some parents a little uncomfortable. According to some press accounts, many parents support the decision. As one put it, "I think at this kind of age a parent should be involved with them because they're so young that they maybe need to be explained what this is about."

Michael Schaub of the LA Times noted that the school's motto is "Preparing Students for a Changing World." Not this time.