Stella the Mouse, Nico the Toad, Delilah the Spider, and Bo the Parakeet are all delighted that today is the first day of school, and the children will be back--but some of the children, the new ones, seem nervous and unhappy, so the four school friends set out to find some way to make those children feel welcome.

Stella the Mouse, Nico the Toad, Delilah the Spider, and Bo the Parakeet are four animal friends that live in the school; Stella came in from the outside, Nico was a classroom pet (until he escaped), Delilah hatched in a corner of the teacher's lounge, and Bo goes home with his human (a teacher) on weekends--but they all love watching the students work and play, and at night they have each other.

On a backpacking trip with her aunt and uncle, a young girl collects rocks while hiking in the forest, by the river, and at the lake, but when her pack becomes too heavy too carry, she finds the perfect solution.

Stella the Mouse, Delilah the Spider, and Bo the Parakeet try to cheer up Nico the Toad by agreeing to join him on a school field trip to the art museum.

Unnoticed by humans, Stella the Mouse, Nico the Toad, Delilah the Spider, and Bo the Parakeet compete, in their own special ways, during the school's Field Day.