Left behind when his family goes to the beach, Montezuma the dog gets revenge by bringing home a scruffy dog he meets in the park and giving him the run of the house.
Aaron and his brother Ryan select two worms as pets for the summer, but as soon as they put them down for a race, their pets disappear underground, not to be seen again until the rainy first day of school.
Third grader Jamie's dream of raising mice as pets is threatened by his sister's ugly cat Caliban, and by his partner and older brother Gordon's notion of selling the baby mice for profit.
Because of his little sister's allergies, J.B. doesn't have a pet to enter in his fourth grade class parade, but he has to come up with some idea to beat the bully who is always picking on him.