Every Halloween Harry plays tricks on his classmates and dresses up as something scary or gross or both. He's been Count Dracula, a slimy snake and even the Loch Ness Monster. Everyone in Room 3B is waiting to see what Harry will be this year--and they're all in for a really big surprise! "There's laughs aplenty in the short snappy text--just the thing to turn new readers on to books."--Booklist for Horrible Harry and the Green Slime

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?

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.

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.

When the post office has donated a real mailbox to room 3B, everyone gets jobs as sorters, stackers, and carriers. ZuZu is in charge of the misaddressed, or dead, letters. But Harry discovers that a thief is using the mailbox for something other than letters. Will he sort out what?s going on? Or will Harry deliver some horribly wrong conclusions?

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 to cheat at the Spring Book Fair Raffle! This is Harry’s chance to stop the horrible bully and prove that he deserves a special star. Can he do it?

The kids in Room 3B are holding a Sharing and Caring Tag Sale to earn money for charity. Song Lee and Ida are selling friendship bracelets, Doug is selling books, and Sid is selling delicious, fresh-baked chocolate chip cookies. But something else is on Harry's mind: his grandmother is having money trouble, and Harry wants to help. So he comes up with a plan to raise money for her. The problem is that Harry doesn't realize his plan involves stealing from the class's charity collection! How can Doug stop his friend from becoming a horrible thief? Could the answer come from one of Sid's delicious cookies?