Subverted: A bully specifically targets Alice, assuming she's easily going to get angry because of her hair color, but she ignores the teasing calmly because Alice is an Emotionless Girl, a mellow redhead if you will.
Double Subverted: But the bully should have remembered to Beware the Nice Ones because when he is least expecting it, Alice punches him in the face and unleashes a Cluster F-Bomb.
Everyone in the anger management class has red hair.
Alice is a Shrinking Violet with red hair. But because the area she's in doesn't have many redheads, everybody thinks of her as The Dreaded and won't dare insult her for how they think she'll react.
Zig Zagged: A bully targets Alice but she ignores him, until he goes too far and she Groin Attacks. However, she is calm while berating him, showing that her temper is still in check, until the bully says something completely unrelated and unintentional and she Megaton Punches him out of town.
Averted: Either Alice is no more hotheaded than any other character or there are no hotheaded characters in the cast.
Enforced: Give Alice a temper, people won't believe she's a real redhead without it.
Lampshaded: "Look out for Alice's temper," Bob warned, "She's just like a typical redhead."
Invoked: "You don't want to make me angry! I'm a redhead!"
Alice and the gang need a distraction, so they stage a scene where Alice has a screaming fit, knowing everyone will buy the act since she has red hair.