A stereotype is a group of qualities assigned to groups of people, and they can be positive or negative. They can be related to race, gender, sexuality etc. Some common stereotypes, especially addressed in film, include women being weak, teenagers being in gangs and unattractive people cast as villains.
In our film opening, we are introduced to three characters - one protagonist and two antagonists. Our protagonist conforms to stereotypes, as she can be viewed as weak, as she is often alone and is upset and jealous of the two antagonists. She feels as though she isn't good enough, and this is a stereotypical and common view that main female characters believe in popular teen films.
The two antagonists - myself and Monique - don't conform to stereotypical views of girls, as they are confident and aren't weak. However, they do conform to stereotypical views of teenagers. In their introduction, we see them steal clothes from a shop, which comes from stereotypical views that all teenagers misbehave and "are up to no good".