The Baby-Sitters Club Wiki
The Baby-Sitters Club Wiki

Science Fair is the seventh book in The Kids in Ms. Colman's Class series. It focuses on student Bobby Gianelli.

Back Cover[]

The kids in Ms. Colman's class are working on science projects. Bobby's group is studying a mouse named Harriet. Harriet is about to have babies. But then Harriet disappears. The science project is a big mess! And everyone thinks it is Bobby's fault.


Main Plot[]

At recess one day, the boys and girls in Ms. Colman's class are playing softball against each other. Bobby enjoys playing sports much more than he enjoys school. When the boys win the game, Karen Brewer accuses the boys of cheating. Karen drives Bobby crazy and Bobby considers her a sore-loser know-it-all.

Bobby acknowledges that other kids consider him a bully, with some being afraid of him, and Karen being one of the few who stand up to him. That afternoon, he and his three-year-old sister Alicia Gianelli play freeze tag in his backyard. When 8-year-old Doug, who lives across the street, mocks Bobby for playing with his little sister, he makes a fist and threatens him.

The next day Ms. Colman announces that Stoneybrook Academy is going to have a science fair, and the kids in her class will work in groups, with three and a half weeks to complete their projects. The two best projects in each class will be displayed in the gym, and a prize will be given to the best project in each grade. To Bobby's horror, he is assigned to work in a group with Karen and Sara Ford.

Karen and Sara talk excitedly about project possibilities, while Bobby responds with sarcastic remarks to anything they say. He says to his groupmates that science projects and science fairs are stupid. However, he secretly feels that although he does not want to write a report about an animals, he does like animals quite a lot. Eventually Karen comes up with the idea to study a pregnant mouse, and the group agrees. Ms. Colman feels that that is a fine idea as long as they can find a mouse that will have babies soon, since the science fair is only in a few weeks.

The next day after school, Sara, Bobby, Karen, Ms. Colman, and Karen's mother go to Pet Time, a new pet store in Stoneybrook. Angela Boone, the owner of Pet Time, gives them a pregnant mouse they name Harriet, under the agreement that they will return Harriet and the babies once Harriet has had her babies.

The groups start to work on their science fair projects. All the kids want to hold Harriet, but Sara and Karen won't let them. Bobby wishes he could just watch and take care of Harriet, rather than have to study her by weighing, measuring, and writing. Karen and Sara are mad at Bobby for not doing the project work he was supposed to do. They tell him they are going to tell on him to Ms. Colman, but he threatens to beat them up at recess, so they decide not to. He tells Harriet he is sorry she has to be a science project.

One morning, Hannie Papadakis arrives early in hopes of getting a chance to hold Harriet before Karen or Sara or Bobby arrive, since they never let anyone near Harriet. She discovers to her shock that Harriet is missing, and the rest of the class start searching for her. When Karen arrives, she accuses Bobby of taking her. When the class can't find Harriet anywhere, Ms. Colman says they need to go to the pet store again.

When they get to Pet Time again, Angela, the owner, is not there so they talk to a teenage employee named Jim. Jim gives them a mouse he thinks will probably have babies, but he doesn't appear too confident about it. They buy the mouse, which they name Hunca Munca, after a mouse in a story by Beatrix Potter.

The morning that everyone needs to be done with their projects before the judges arrive that afternoon, Karen, Sara, and Bobby are demoralized about their project. Karen and Sara blame Bobby for Harriet having escaped, and the status of their projects. Bobby looks around the room at the other projects and feels that his group's project is the only disaster. The judges come by and pick two of the five projects to be displayed at the science fair, neither of which is Bobby's group's project.

The science fair is held at the Stoneybrook Academy gym. Bobby meets up with Ricky, whose project gets a star for an honorable mention, even though the second grade winner is from Mr. Berger's class.

On Tuesday afternoon, Ms. Colman and Bobby's group return Hunca Munca to Pet Time. This time Angela Boone is there and she laughs while explaining that Hunca Munca is not going to have babies, since he is a boy. Bobby continues to worry about Harriet, and wishes he had a pet of his own.

Another day a while later, Omar points out something in the coatroom. When Bobby looks closer, he finds Harriet and nine of her babies. The kids crowd around the shoebox to look, and Karen laments that they didn't find Harriet before the science fair. Ms. Colman takes the shoebox with Harriet and her babies puts them back in Harriet's cage. The kids can't stop talking about Harriet and her babies, and Karen continues to accuse Bobby of letting Harriet out of her cage. This leads to Audrey admitting that she accidentally let Harriet out of her cage when she was in the classroom after school and wanted to hold Harriet, which she never could before because Karen, Sara, and Bobby would never let anyone else near Harriet. Karen apologizes to Bobby and Bobby considers reacting meanly, but decides not to because he is mostly just glad Harriet is back.

A few days later, Ms. Colman, Mrs. Giannelli, Sara, Karen and Bobby go back to Pet Time to return Harriet and her babies. Angela can finally give them the money back for Harriet, since she has now been returned. Bobby sees his mother pointing to a cage, and Mrs. Gianelli tells him that she is buying Harriet for him to keep. Bobby is happy that he finally has a pet of his own.

Secondary Plots[]

Bobby wants a pet of his own, which is finally resolved when his mother buys him Harriet at the end of the book. He also cares more about caring for animals than he does about school or the science project, while Karen, from Bobby's perspective, seems to care far more about the project and accusing Bobby of sabotaging it than she does about Harriet herself.

Characters In This book[]


Science Fair Project Groups

  • Bobby, Sara, Karen - studying a pregnant mouse
  • Ricky's group - Our Solar System - a model of the solar system, won an honorable mention
  • Natalie's group - model of the Grand Canyon
  • Tammy, Hank, Nancy - either:
    • Plants and How They Grow or
    • Last group - project about birds

Other Kids

  • Doug - kid who lives near Bobby

Bobby's Family


  • Jim - teenage employee at Pet Time


Places In This Book[]

Continuity and Inconsistencies[]

  • Bobby’s family has a dog, but their dog is only briefly mentioned twice, and not by name. Before he gets to keep Harriet, Bobby laments that he does not have a pet of his own.


  • Bobby's group buys and then returns a mouse named Hunca Munca to the pet store. In Karen's Candy, Mr. Posner's class has two mice in a cage: Hunca Munca and Stuart Little. However, this is probably just a coincidence and is not meant to refer to the same mouse.
  • On the dedication page it says: "This book is in honor of the birth of James Holton Gibbel. Welcome, James!"
  • Bobby took Hootie home for the weekend before..
  • Bobby thinks that Natalie is okay, Ms. Colman is an okay teacher, and Karen is his least favorite person in class.
  • Sara Ford is new to Stoneybrook Academy this year.
  • Pet Time is a new pet store in Stoneybrook.
  • Pop culture and real life references include: Peter Rabbit, Ralph S. Mouse, Stuart Little, Beatrix Potter, Hunca Munca
  • The projects that got to be part of the fair in Ms. Colman's class includes: Our Solar System and Plants & How They Grow
  • A news crew from the paper came to report on Stoneybrook Academy's science fair
  • The second grade winner at the fair was from Mr. Berger's class
  • Inconsistencies: an adult is a hall monitor in this book (Mr. Fleming) while in Karen's School Mystery it's student hall monitors.
  • Bobby's mom buys Harriet for him at the end of the book.