George (Freddie Highmore) is a fatalistic high school senior who is a gifted artist. George is often haunted by the realization that he will die someday. He ceases to complete his homework, as he feels that everything seems meaningless. As a result, he is put on academic probation. The next day, George goes up to the school roof and sees Sally (Emma Roberts) smoking. When a teacher comes up, George quickly pulls out a cigarette and takes the blame. Sally meets George to thank him, and though George is at first reluctant to talk to her, he soon warms up to her. On Career Day, George meets a young artist, Dustin and is inspired by his thoughts about life.
He brings Sally with him to visit Dustin and it becomes apparent that Dustin likes Sally. Sally invites George to a New Years Eve party. At the party, she dances with her ex, while George gets drunk, puking outside before falling asleep in the alley. Sally finds him there and apologizes. For Valentine's Day, the two go out to dinner and Sally asks him to have sex with her. George, clearly shocked, doesn't answer.
After his pause, Sally says they shouldn't as he is her only real friend. He is quiet for the rest of the time they're together and goes home early. He doesn't answer Sally's calls or talk with her at all. Sally instead invites Dustin out and flirts with him. The two of them start going on dates after Dustin kisses her.
George doesnt do his English term paper and is brought to the principals office. The principal gives George two choices: expulsion or do every piece of undone homework, about a years worth. At home, George confronts his stepfather about lying about work, and they get into a physical fight. George takes off for Sallys place.
She brings him into the hallway, where he kisses her. Sally kisses back but breaks it, revealing Dustin in her apartment. Angry and hurt, George leaves. The next morning, George finds his mother at the park.
She explains that his stepfather lied to her about work and that theyre divorcing. George consoles her and begins to rethink his situation with Sally. At school, he gets each of his missing assignments to complete. His one art project is to make a painting that is honest and real. George completes the assignments and takes final exams, while Sally continues being with Dustin. Sally and George meet in a bar, where Sally reveals she's going backpacking with Dustin through Europe, and is skipping the high school graduation ceremony. George tells her he loves her and they go back to her apartment, where they kiss.
Sally admits she loves him as well, promising that they will be together one day. George triumphantly turns in all his assignments and his art teacher applauds him on his art project. At the ceremony, Georges name is called and his mom is shown to be proud of him. George goes back to the art classroom and looks at his art project: Sally's smiling face.
Sally, having opted not to go to Europe with Dustin, enters the room and looks at the painting with George and the film closes..