Act One

It's the last day of junior year, and the East High gang can't wait to get the summer started. They anxiously watch the clock tick towards 3:00 PM, as they think about all the things they want this summer: summer jobs, money for college and, most of all, to have fun ("Countdown / What Time Is It"). Things have been smooth sailing for Troy and Gabriella since their star turn in Juliet & Romeo, but Sharpay vows to win Troy's heart this summer... by any means necessary. Ryan tries to remind her that she is supposed to be the "new" Sharpay who loves everyone and is loved by everyone in return, but she can't help reverting to her old self. With all of the Wildcats desperate for cash, Troy gets a surprise phone call that work has arrived.

At the Lava Springs Country Club, which is owned by the Evans family, Sharpay revels in her summer kingdom, surrounded by the club staff and her adoring Sharpettes ("Fabulous"). The celebration is cut short when not only Troy, but the entire Wildcats gang, shows up for duty. Sharpay had been hoping to get Tory on his own this summer, but now she has Gabriella to contend with. Meanwhile, she tells Zeke that they should take a break from each other; in the summer, everything changes. Sharpay tries to get the assistant club manager, Mr. Fulton, to fire everyone, except for Troy. However, he insists that, once she's had them hired, he can't just fire them; this is a place of business. She reminds him that her father has told him to do whatever she wants this summer, and he agrees – begrudgingly – to make life difficult for the Wildcats.

Mr. Fulton assigns the East High gang a series of tough jobs, starting with cleaning up the kitchen. When everyone is dejected that this summer is going to be much less fun than Troy promised, he reminds them that they're all in this together and, together, they can do anything ("Work This Out"). Troy and Gabriella sneak off for a romantic, private lunch on the golf course ("Picnic"). Sharpay spies on them and interrupts their fun by having Mr. Fulton turn the sprinklers on them. She is determined to get Troy.

In the dining room, Kelsi plays a song that she wrote for Troy and Gabriella to sing in the upcoming talent show ("You Are the Music in Me"). When the rest of the Wildcats join in, they decide to go for it and present the number in the show; as long as they're all in it together, they might even win the Star Dazzle Award.

Meanwhile, Sharpay arranges for Troy and Chad to caddy for her and Ryan. When they are out on the course, Sharpay mentions that her father is the head of the scholarship committee at the local college. She intimates that, if Troy sings with her in the talent show, he'll have a better shot at the scholarship. He declines because he's already singing with Gabriella, but Chad can tell that he is also thinking about the scholarship.

In the golf pro lounge, Fulton informs Troy that he's been promoted to junior golf pro, which comes with honorary membership status and an extreme makeover ("Fabulous – Reprise"). Sharpay once again tries to convince Troy that singing with her means getting a scholarship, and he reluctantly promises to sing with both her and Gabriella. Ryan chastises Sharpay for thinking only of herself, but she dismisses him. While Gabriella and her friends wait for Troy to show up for rehearsal – he's late again, and he missed dinner with Gabriella – Sharpay and Ryan rehearse their number with the Sharpettes ("Humuhumunukunukuapua'a"). Sharpay is off-key, but she blames everyone around her. When Troy finally shows up, Sharpay demands that he sing with her now.

Sharpay bribes Kelsi into letting Sharpay and Troy perform the song that Kelsi wrote for Troy and Gabriella. Sharpay says that, if Kelsi does this, Mr. Evans will produce her next musical. Ryan can't believe he – and their number – are being ousted for Troy. Gabriella and the gang can't believe Troy sold them out. Everyone breaks into a big fight, with Troy unable to control the chaos around him ("Act One Finale").

Act Two

During the second week at Lava Springs, Troy rehearses Kelsi's revamped song with Sharpay and the Sharpettes ("You Are The Music in Me – Rock Version"). Later, Gabriella finds Troy on the basketball court. He is getting ready to go practice with the University of Albuquerque basketball team. Gabriella confronts him about breaking all of his promises lately, and he finally apologizes. When Chad and Zeke show up and learn that Troy is going to practice with the Redhawks without them, they get very upset. The boys leave as Ryan enters. He and Gabriella have a heart-to-heart about the way Sharpay has treated him. Gabriella invites him to join them in the staff baseball game since they are short a player now that Troy has blown them off.

At the game, Chad is dubious of dancer, Ryan's, skills and allegiance. However, Ryan not only gets Chad to dance, but helps the Wildcats win the game ("I Don't Dance"). Troy shows up just in time to see his friends celebrating without him. Mr. Fulton gives Troy an encouraging, if baffling, pep talk. Now officially part of the team, Ryan teaches the gang a new number for the talent show ("Every Day – Rehearsal"). Sharpay is furious at him for competing against her and vows revenge. Ryan tries to warn Troy about Sharpay, but Troy rudely cuts him off.

Sharpay, feeling her Star Dazzle Award is under siege, directs Fulton to yank the employees from the talent show. Reluctantly, Fulton does. Sharpay basks in the glory of her power ("Fabulous – Sharpay's Triumph"). This is the last straw for Gabriella, though, who confronts Sharpay, quits her job and breaks up with Troy ("Gotta Go My Own Way"). Gutted, Troy goes out to the basketball court and tries to make sense of what is happening to his life ("Bet on It").

The talent show starts with a variety of stage acts. Backstage, Troy decides to set things straight. He gets his old job back from Fulton and tells Sharpay that, as an employee, he can't sing with her, apologizing to the Wildcats. Sharpay throws a tantrum and tries to fire Mr. Fulton, who finally stands up to her and tells her to pull it together. Mr. Fulton allows the employees to sing in the talent show.

Troy goes to see Sharpay, who is eating a plate full of delicious cookies that were mysteriously left in her dressing room. He tells her that he will sing with her now that the employees are allowed to sing, too. He wants to start keeping his promises. Sharpay finds out that the cookies are from Zeke and realizes she has been foolishly chasing after Troy when her guy was right in front of her. Sharpay gets Mr. Fulton and announcer boy, Jack Scott, to stall the show while she makes a few phone calls.

When Troy goes on stage to sing, Gabriella walks out. Sharpay has arranged the switch. Gabriella forgives him on stage as they sing. They bring Ryan and the rest of the Wildcats up on stage for the big number ("Every Day"). It's a success and Ryan wins the Star Dazzle Award. Now reconciled, the entire company celebrates the summer ("All for One").