Invincible

During the 1970s, chaos reigns in the city of Philadelphia as southern portions of the city protest the shutdown of several job sites while their NFL team, the Philadelphia Eagles, endures a string of losing seasons, plus irate fans.
During the spring of 1976, 30-year-old Vince Papale goes to a sandlot one night and joins his friends playing a pick-up practice football game against another group of young men. After the game ends, Papale goes home and finds out that his wife Sharon is upset with his alleged failure to provide proper support.
The next morning, Papale goes to the high school where he works as a substitute teacher. In a short, unexpected meeting with the principal, he is told of his layoff. Later in the day, there is a report that the Eagles have hired a new head coach named Dick Vermeil as shown in a formal televised conference. That night, Papale goes to the bar where he works as a part-time bartender. The bar contains die-hard Eagles fans, who are watching TV about the hiring of Vermeil. The news story concludes with the announcement by Vermeil that he is staging open public tryouts for the Eagles. The men in the bar encourage Papale to go to the tryout. When Papale returns home, he finds out that his wife has left him and a note from her saying he will never be anything in the world. Papale becomes disgusted, smashing the few remaining belongings that Sharon left behind.
When Papale goes to the bar next night, he meets a new co-bartender, Janet Cantrell, who (being from New York) is a Giants fan. Desperate for income in the aftermath of his wife's departure, Papale receives support from his friends and attends the tryout hosted at Veterans' Stadium in Philadelphia. Out of several hundred Philadelphia residents attending the training facility, Papale performs well during the workouts. After the camp is over, Papale fails to start his car and Dick Vermeil comes by. He is impressed by Papaleâs actions at camp and invites him to a roster spot with the Philadelphia Eagles. Everyone at the bar becomes excited about the TV announcement that Papale will be joining the team. After work, Papale has an interview with a newscaster.
The next day, Papale exercises by jogging in the city and stops by at the empty home he tore up, where his former wife Sharon lived; then he interacts with his friends, telling them about joining the Eagles. His father meanwhile offers to let Vince stay with him. The following day, he goes to his first training camp with the Eagles. As the days of training camp progress, Papale endures a life full of hard work and disrespect from the other players. Papale goes out on a date with Janet one night, but didn't think he'd still be on the team. He says he's not sure he can start a new relationship at that time because he's focused on trying his best to make the team and she claims she didn't know it was a date. She goes to help out at the bar and he leaves.
As Papaleâs career with the Eagles begins, the team loses all six preseason games and their regular season opener against the Dallas Cowboys. After the team returns to Philadelphia, Papale goes to the sandlot where he played with his friends several months before. He is invited to play, but he declines because of his upcoming Eagles game and watches for a few minutes. A rainstorm begins, and then Papale does join his pals and plays against another sandlot team to help his friends. During a wet and dirty game, Papale ends the game by throwing a touchdown pass. When he runs into Janet later, they speak briefly before passionately embracing and tumbling into Vince's home.
During the home opener against the New York Giants, Eagles fans are enraged about Janetâs appearance in a Giants shirt. She does not back down. In the locker room, Vince looks again at the note Sharon had left and tears it up. Papale opens the game by solo-tackling the kickoff returner inside the 15-yard line. After an up-and-down game, Papale gets downfield during an Eagles' 4th quarter punt to tackle the returner, forcing a fumble that he recovers and takes into the end zone for a touchdown, giving the Eagles their first win in Papaleâs career. Eagles fans go wild with joy. As the film's end credits appear, media and actual footage show highlights of Papaleâs career with the Eagles (including an apparent touchdown scored by him, which was disallowed due to the fumbler being ruled to have "muffed" the punt).

Question: Who works as a substitute teacher?
Answer: Papale.