The story begins with a five-year-old green caterpillar entering Kindergarten. It soon discovers that school is full of unexpected friends, and each one has something important to teach.

The first is the Alphabet, helping the caterpillar begin its journey with letters. Next comes the Kindergarten math book, introducing numbers, shapes, counting, taking away, telling time, coins, patterns, sorting, and graphing. Then the Kindergarten phonics book shows how letters and sounds come together to form words.

In January, the caterpillar meets Kindergarten friendship and learns that growing also means working together, sharing, caring, and respecting friends. The Kindergarten reading library follows, bringing stories into the journey. Then comes the Kindergarten science center, where the caterpillar learns about seasons, weather, and growing and changing.

By April, the Kindergarten writing journal becomes the next friend. The caterpillar draws pictures, writes sentences, learns where letters belong, and discovers more ways to express what it knows.

Then comes May. The caterpillar meets the night sky, whose lesson is simple: children need rest so they can learn and grow. The caterpillar falls asleep after its Kindergarten journey.

When it wakes, the school year has transformed more than its knowledge.

It has transformed the caterpillar itself.

The Kindergarten caterpillar has become a first-grade butterfly.

The book also includes a song for each learning area, making the story especially suited to its original purpose as a Kindergarten graduation play.