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.

Horrible Harry of classroom 2B cuts back on his mischievous pranks after falling for Song Lee.

When their teacher ends up in the hospital, the members of class 2B find a way to include her in their holiday celebration.

It's almost summer vacation and the students in room 2B are having trouble concentrating on their butterfly project, until a frightening-looking new teacher comes to supervise the Suspension Room and Harry is sent there as punishment for unruly behavior.

On the last day of second grade, Song Lee's party at the local amusement park forces Harry to face his fear of elevators when he is expected to ride the Drop of Doom.

Inspired by his third-grade class's study of the moon, Harry announces that he is going there.

The students in Miss Mickle's third-grade class enjoy a boat trip on the Connecticut River after a class discussion of ancestors reveals that Sidney and Ida both have connections to the sea.

Best-selling children's author Suzy Kline delights listeners of all ages with this fun addition to the acclaimed Horrible Harry series. The kids in Room 3B are in an uproar. That rascal Harry is at it again-and this time, he might have gone too far! It all starts when Harry comes to school with a mini-microscope that everyone wants to try. Harry agrees to put on a show with it at recess, but he wants to look at mushrooms on the other side of the school...

Harry and his detective classmates try to find clues relating to a mysterious locked closet in Room 3B.

Horrible Harry sets out to discover who Miss Mackle is going to marry, and he takes some risky moves to be the first one to know.

Horrible Harry must defend his reputation as a detective by cracking the secret code of Mrs. Funderburke's lunch prizes.

Harry and Doug investigate when special bookmarks begin to disappear while their class is busy studying poetry and running their own post office.

While Harry's third-grade class is studying birds, the cold winter weather keeps them cooped up inside during recess and Harry gets restless.

When the origami pig that Song Lee made for her grandmother is seized by a substitute teacher, the usually well-behaved third-grader breaks a classroom rule to rescue it from the "June box."

"Harry considers stealing from Room 3B's Sharing and Caring Tag Sale in order to help out with money problems at home"--

Nearly every kid in Room 3B is trying to get picked for the South School Safety Patrol Squad--especially Harry. Harry wants a star badge just like his grandpa's, so he works extra hard to be the perfect student: hanging up his jacket neatly, organizing the crayons in rainbow order, and--his favorite part--cleaning up sticky noodles off the floor after lunch. But Doug thinks someone is taking the power of Safety Patrol too far, maybe even using it...

"When his best friend Doug discovers his top-secret hideout, Harry enlists his friends' help to save it from being developed into an apartment building"

As the last day of third grade looms, Doug learns that Harry is moving to a new town and wonders how he'll survive fourth grade without him, while Harry wonders about the new neighbors across the street and what they could mean for their friendship.