Horrible Harry is at it again in his rollicking 36th story as he and his classmates participate in South School's Field Day! That means bean bag tosses, relay races, tug-of-war, and a mystery prize. Harry and Doug are determined to win, but at what cost? Original.

Horrible Harry has caused a lot of trouble at school before, but he's never caused trouble like this. When Sid ruins an origami animal Song Lee made, Harry defends her by declaring triple revenge! No one knows when, where, or how, but Harry is going to get Sid back. Will it be on pajama day, when the kids wear their nightclothes to school? Will it happen in Room 3B? Or will Harry's ultimate revenge mean Sid is the only one not invited to Harry's ninth birthday party?

Third grade brings lots of surprises, but one thing hasn't changed a bit--Harry and Sidney are still sworn enemies. And their relationship only gets worse when Sidney accidentally kills Harry's pet spider. But Harry comes up with a horribly funny way to get revenge during a class trip to a creepy copper mine.

When Sid, his annoying third-grade classmate, ruins Song Lee's origami praying mantis, Horrible Harry plots triple revenge on the troublemaker.

After four days in a row of indoor recess, Miss Mackle's students are bored-until Harry decides to solve the biggest mystery ever in Room 3B! There's a locked closet in the classroom that's been sealed off for years, and he wants to know what's inside. So Harry drafts Doug, Song Lee, and the rest of the class to help him investigate. Their search reveals many surprises-from a hidden trapdoor to...eyeballs! What secret treasures does the closet hold? Is it something more horrible than even Harry can imagine?

Another fun mystery starring Horrible Harry, and this time he's calling the shots! Harry has always loved solving mysteries, and now his friends in Room 3B have learned to love it, too. So Harry challenges them to figure out what he has hidden in his giant, old suitcase. Led by a very determined Mary, the kids take turns solving clues and piecing the mystery together. Their hunt leads them from the classroom to the library, and even to Harry's grandfather's nursing home. Will they be able to solve Harry's mystery? Or will things go horribly wrong for the novice detectives?

Doug discovers that though being Harry's best friend in Miss Mackle's second grade class isn't always easy, as Harry likes to do horrible things, it is often a lot of fun.