During Spring Break, mystery lover Amy looks for clues to the disappearance of wealthy Ms. Sullivan's Saint Bernard puppy.

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.

"Amy is excited to meet her new stepsister Chloe, but as the girls get to know each other, Amy realizes Chloe isn't as nice as she appears to be in front of the grown-ups"--

"Liz can't wait to spend the weekend with the Critter Club at her house on Lake Marigold, but when all the activities go horribly wrong, Liz worries the weekend will be a disaster"--

"Amy comes up with the perfect Christmas present for Mrs. Sullivan to cheer her up and give her some company"--

As her friends in the Critter Club animal shelter care for colorful aquarium fish, second-grader Liz and her family spend a long weekend at the beach, where Liz rescues a baby octopus and competes with an unfriendly young neighbor in a sand castle contest.

"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!"--

When Liz and her friends have a sleepover at the Santa Vista Art and History Museum, they investigate the source of strange noises they hear at night and get a big surprise.

Unless Amy and her friends in the Critter Club can come up with an alternative plan, new stores are going to be built on the town's park, endangering the lives of the plants and animals living there.

"Liz has been assigned a class project that's perfect for her. She has to create a diorama of an animal habitat! Art plus animals? What could be better? Well, things could be better if Liz's new neighbor and classmate was a little nicer to her ... and a little less nosy!" -- Back cover.

"When Amy meets the owner of a brand-new puppy at her mom's vet clinic, she agrees to help the woman train her new pet. Amy does such a great job, she starts getting calls from more puppy owners! Things go great for a while, but soon, Amy is in way over her head. She can't say no to a puppy in need and has taken on way too many clients! Amy barely has time for school or her friends in between all the puppies. Can she dig herself out of this hole before...

Liz and her friends are spending a fall weekend at the cabin at Marigold Lake, planning to bake pies and enjoy nature, but Lizzie forgets to put sugar in her berry pie--a mistake which proves fortuitous when she needs a lot of berries to feed a migratinggoose who has fallen behind his flock.

Amy is excited for her step-sister to visit, but when everyone, including the snake the Critter Club is watching, seems to love Chloe, Amy starts to wonder if they all like Chloe more than they like her.