Members of the Critter Club are all excited about their summer plans until Liz learns that, instead of taking an art class, she will have to be in summer school to improve her math skills, but a fun teacher, a classroom pet, support from her friends, and advice from her brother might get her through.

Liz is excited for her sleepover at the museum until she hears some spooky noises that may turn this sleepover into a nightmare.

When she wins the lead role in a school play, second-grader Ellie neglects her friends in the Critter Club and their new animal shelter

When Marion finally gets the chance to babysit her little sister, she finds that the task is harder than she expected, especially when she gets called to the Critter Club to help with a stray cat and must bring Gabby along.

"Amy has never liked being in the spotlight. When all her friends decide to form a team for the Santa Vista Quiz Bowl, Amy's not so sure. She knows she can answer the quiz questions ... but can she do it in front of hundreds of people? Meanwhile, The Critter Club is caring for some chickens who need a home. As the Quiz Bowl approaches, Amy herself starts feeling just a little bit chicken!"--

"Ellie has always wanted to go to wedding, and her hopes finally come true when her cousin asks her to be a flower girl at her wedding. Then the Critter Club gets the cutest guest Ellie has ever seen: a little French bulldog. Ellie works hard to find a home for the puppy, but she's worried she won't be able to. Suddenly she has an idea that will guarantee that the puppy lives happily ever after!"--

Taking a turn caring for the class pet hamster, Marion is devastated when the hamster goes missing and she receives an anonymous letter in her locker with clues leading to a mysterious scavenger hunt.