L'événement culturel de l'été à Bruxelles!
Twelve-year old New Yorker Evan Goldman is surrounded by rabbis. After chanting to him, one of them explains that when a boy has his Bar Mitzvah, he becomes an adult. As the rabbis reveal that they are actually other New York kids, Evan tells the audience about how stressful turning thirteen is – especially since his parents are getting divorced and he is under pressure to have the best Bar Mitzvah imaginable Thirteen/Becoming A Man). Just as Evan thinks that maybe things will be fine, his mother calls to tell him that they are moving to Indiana. Once there, however, Evan finds a friend in his neighbor, Patrice. Evan is very disappointed that there are no cool places to have his Bar Mitzvah; Patrice agrees that their town is lame, but things have gotten better since Evan moved there The Lamest Place in the World.
When school starts, Brett, the most popular kid in school, summons up the courage to ask Kendra, the prettiest girl in school, to a scary movie Friday night so that he can kiss her with tongue Hey Kendra. Despite her best friend Lucy's attempts to dissuade her, Kendra consents. Inviting Kendra to a scary movie was Evan's idea, so Brett decides that Evan is cool and refers to him as the "Brain." Evan is thrilled; this means that Brett will come to his Bar Mitzvah, and if Brett comes, everyone else will come. Patrice, however, is displeased. If she goes to the Bar Mitzvah, nobody else will go because all of the others hate her. Evan does not think that it will be that bad, but when he hands out the invitations, he sees that Patrice is right, so he rips up her invitation. As the other kids express their excitement over Evan's party, Archie enters and introduces himself. He is upset at Evan for humiliating Patrice – his best and only friend – but promises to help to make it up to her if Evan gets him a date with Kendra. When Archie’s attempts to use his degenerative illness to guilt Evan into getting him the date do not work, Archie tries to convince him that he can turn to no one else Get Me What I Need. Evan finally relents. Later, at cheerleader practice, Kendra teaches a new cheer while Lucy resolves to make Brett her boyfriend Opportunity. Archie tries to talk Patrice into giving Evan a second chance, especially since she has a crush on him, but she has lost faith in him What It Means To Be A Friend.
In class, Brett tells Evan to get his mother to buy them all tickets to "The Bloodmaster." Evan protests that his mother will not buy them tickets to an R-rated movie, but Brett points out that if she does not, nobody will go to his Bar Mitzvah. Evan cycles through possible plans, eventually settling on having Archie use his illness to guilt his mother All Hail the Brain/Terminal Illness. To make things better with Patrice, Evan asks her to go to the movie with him as a date. He then realizes that he set up Archie’s date with Kendra when everyone is seeing "The Bloodmaster," which is Kendra's date with Brett. Evan makes Archie promise to do nothing more than sit next to Kendra so as not to screw up Brett's date. Archie agrees, and everyone prepares for Friday night Getting Ready.
At the movie, Patrice is upset that Evan is not even sitting next to her. Brett and Kendra overthink their impeding kiss, and just as they are about actually to do so, Archie ruins it Any Minute. Brett swears revenge on Evan and Archie, and Lucy, seeing her chance, kisses Brett. Patrice tells off Evan when she sees that all that he cares about is Brett’s being angry at him Good Enough. Even Archie is upset with Evan, who then realizes that he is in danger of being a lonely geek Being a Geek. As Lucy and Brett begin dating, she forces him to spend increasingly more time with her. Brett's friends recognize that Lucy is good neither for Brett nor for them at all Bad Bad News. Evan promises to help to get Brett and Kendra back together so that he can get back on everyone’s good side. Archie, fearing that this is a suicide mission, begs Patrice to help Evan. She shows up just in time to tell Brett to talk to Kendra, and she and Evan suggest things to say – while resolving their own issues Tell Her. Charlotte, a member of the cheerleading squad, comes in and tells Brett to quickly come to the girls bathroom. He finds Kendra and Lucy fighting in the bathroom while Charlotte stands by and watches. As Kendra is about to walk out, Brett tells Lucy that he wants Kendra. He tells her that she is the one he wants to be with and that he likes her and they get back together. Lucy, however, will not stand for this. She spreads a rumor that Kendra is cheating on Brett with Evan, and then gets Evan and Kendra in the same place so that Brett can catch them It Can't Be True. Her plan works. As Kendra runs after Brett, Evan realizes that he did not really want to be friends with Brett anyway, and that Archie and Patrice are his real friends. He wants to call off the Bar Mitzvah because it would only be the three of them, but Archie and Patrice point out it that will not be that bad If That's What It Is, when Evan kisses Patrice out of nowhere, and learns that making wrong choices is all a part of growing up. Evan has his Bar Mitzvah after all; he is starting to understand what growing up means A Little More Homework. The show ends with the cast singing Brand New You.