Humphrey the hamster is puzzled when unfamiliar students fill Mrs. Brisbane's classroom at summer's end, but he soon learns that his friends from last year are fine and that the new class needs his special help.

After learning about Sherlock Holmes, Humphrey the classroom hamster follows clues to try and discover why Mrs. Brisbane is gone and Mr. E, a fun but not very educational substitute, is taking her place in Room 26 at Longfellow School.

Humphrey, the pet hamster of Longfelow School's Room 26, learns that his classroom is full of secrets, the most important of which is that a student will be leaving soon.

"A pet hamster is enticed by the family cat to venture outside his well-equipped cage to the sunroom only to very quickly discover life outside his cage is not the best for him."--

Humphrey, the pet hamster of Longfellow School's Room 26, relates the ups and downs experienced by his human classmates as they begin a project to create a model town complete with houses and community services.

With more than one million copies sold, this series has been a huge Scholastic Book Clubs success. Klein presents a diverse community of 1st graders facing real issues that matter to this age group.All the kids in Freddy's class want to be chosen to take home the class hamster for the weekend. Freddy can hardly believe his good luck when he is chosen. But he's forgotten that his mom is a total Neat Freak and can't stand the idea of having animals...

"Matt Hunter is expecting the latest sword-and-fantasy video game, but he's in for a disappointment when he receives a hamster for Christmas instead. A hamster called Snuffles. A hamster that dies, but somehow keeps going. A zombie hamster that has his eye on Matt"--

Little Hamster has no friends because he hits so he has to learn to play nicely.

On Groundhog Day, the students in Mrs. Connor's class try to find out whether the class hamster can predict the weather as well as a groundhog.

During their trail ride on all-terrain vehicles, Hot Rod Hamster and his friends stop to help Grandpa Dog and two puppies, whose vehicle has tipped over and gotten stuck in the mud.