Live ants are coming to Room 2B, and Harry gets to take care of them when they arrive. He'll get to help the teacher transfer all the ants to their new home in the classroom where everyone can watch them. Can trouble be far behind?

As Valentine's Day approaches, the students in Room 2B are preoccupied with kickball and a possible wedding between Horrible Harry and Song Lee.

Horrible Harry falls in love with Song Lee, and Harry's best friend, Doug, can't stand all that mush.

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.

Horrible Harry and friends start off third grade with a new room and a field trip to an old copper mine to study rocks.

The students in Miss Mackle's third-grade class enjoy a day of Halloween surprises, including Harry's unusual costume.

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.

Harry persuades his classmates to sneak through the playground fence during lunchtime recess to view some unusual mushrooms.

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

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