Now that's she's been in school for a while, Junie B. Jones has decided to write down everything she knows for future first graders ("Junie B.'s Essential Survival Guide to School"). In Mr. Scary's classroom, everyone is excited about Junie B.'s idea to write a guide, but May teases Junie B. about not knowing what to write in it. Junie B. struggles to come up with ideas to prove May wrong ("Like What?"), but fellow classmates Lucille, Sheldon, and May manage to chime in with ideas of their own.

Because she called May mean names in class, Junie B. has to go home with a note from Mr. Scary. Junie B. explains to Mother that she doesn't want other people to help with writing the guide because she wants to be "the star of the whole production". Mother tries to explain to Junie B. that being the star isn't important.

Meanwhile, May, Herb, and Sheldon are brainstorming about what to write in the guide. Sheldon tells Junie B. and everyone else about his vision for a parade devoted to backpacks ("Backpacks on Parade"). Everyone loves this idea - except for Junie B., who is upset that she didn't come up with it ("A Great Idea").

Junie B. has come home with yet another note. She tells Mother that it's not her fault. Her tendency to get in trouble, she explains, comes from a bull in her stomach ("El Toro Fabuloso").

In the school lunchroom, Lucille interviews Junie B. about clothes ("Some Stuff About Clothes"). As part of an example, Junie B. spills spaghetti on May, which means taking a note home again ("El Toro Fabuloso Reprise"). At home, Mother, Daddy, and Grampa Miller explain to Junie B. that even if she doesn't like May, she has to be respectful to her.

The next day at school, May and the rest of her classmates put on a show about school supplies ("School Supplies"). At first, Junie B. tries to be nice and follow the script, but that quickly derails as she makes fun of May's excitement about school supplies, ruining the show. Furious, Mother makes Junie B. write an apology letter to May ("Dear May").

Junie B. rushes to get on the bus ("Gotta Get There"). Once she gets on, Herb tells her that his chapter in the guide will be about what you can do on the bus ("Bus Rules"). Junie B. tells Herb that you can also make funny faces on the bus. As she keeps making funny faces out of the bus window, a woman takes photos and notifies the school - landing Junie B. in the principal's office ("Principal's Office").

The principal, teachers, and Junie B. go over the rules she's supposed to follow ("Rules!"). Principal tells Junie B. to give May her apology letter but then gives her a surprise: for the rest of the day, there will be no rules in Junie B.'s classroom. Junie B. and the rest of the class are overjoyed. Their joy is short-lived, though. While Mrs. Gutzman passes the class without giving them their daily cookies, she tells them that since getting cookies was a rule, there will be no cookies today. They realize that maybe rules aren't so bad after all.

The school year is almost over, and one thing stands between Junie B. and summer - "Report Card Day". Junie B. is burying her report car in someone's yard when Mother finds her and asks her why she is doing this. Junie B. tells her that she thought that she knew everything but now realizes that she needs to improve herself more. Mother comforts her and tells her everyone needs to work on improving themselves, but Junie B. is still upset that she can't figure out what to write about in the guide ("Junie B.'s Lament"). Mother then shows her a report card from her own childhood, revealing that she was also a troublemaker ("Mother Was a Bad Kid Too"). May shows up at Junie B's house, and they reconcile ("That Does Make One Feel Better"). Junie B. realizes that she can write a chapter on not getting in trouble for the guide since she's learned so much about that ("The Things You Learn Along the Way").