It?s the last day of second grade for the kids in Room 2B!Everyone?s excited about Song Lee?s end-of-the-year party at Mountainside Park. Harry can?t wait for the scary rides, so when Sidney dares him to go on the newest one he quickly accepts. But then he realizes that this ride has the one and only horrible thing he hates. Will Sidney show everyone Harry?s a yellow canary? And will Harry have to live through third grade at Sid?s mercy? ?As always, Harry?s appeal is that he?s both ?gross? and vulnerable.? ?Booklist for Horrible Harry?s Secret

Harry leads a mission to place cobwebs all over school, shows the class how to make green slime, and stages a "deadly skit" that has everyone on the edge of their seats.

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.

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?

It’s a horrible day for Harry: a classmate is calling him names; his library book is overdue; he’s last in line for a turn to be the Room 3B VIP. Worst of all, it’s cold and icy outside again, which means no outdoor recess. It’s all too much for Harry—he starts to go cuckoo! Fortunately, there is a solution to Harry’s problems . . . but it comes from a very unexpected source.

Harry's in love, and his best friend, Doug, is disgusted -- Harry won't even throw snowballs at girls anymore. Will Harry ever go back to being his horrible self?"Kline captures perfectly the crowd scenes and private moments in the classroom."-- Booklist

The holiday season is here, and the kids in Room 3B are learning about all the different ways people celebrate. In addition to Christmas and Hanukkah, there's Kwanzaa, Three Kings Day, Korean New Year, and more. All the talk about holidays has everyone feeling festive. Everyone, that is, except Harry. He doesn't seem to care about the holidays, the class pet, or even the new student in class. It's clear that something is bugging Harry—but what could it be?