The mascots change about four times I believe, from names such as Trojans and Devils and Hornets. The principal changes these mascots so many times because he is striving to find one that is "safe" and "appropriate." However, while he is wasting his time changing mascots, the students are having real issues. Melinda was raped, but the principal is clueless, trying to find politically correct mascots. The changing of the identities of the mascot also reflects Melinda's uncertain identity, as she holds on to the secret of her rape.
Speak is the story of Melinda, a freshman at Merryweather High School, who is carrying around a secret from the summer. She has lost touch with all of her former friends, and only refers to the event as IT. Melinda struggles in all of her classes, except art. No one seems to notice or take an interest in why Melinda is feeling the way she is; their main focus is on the ever changing mascot of the High School.
The higher ups at the school want to make sure the mascot is one that will be politically correct. Their main focus has been on that, which is ironic, because while they are concerned about the mascot, they have a student who is going through this major trauma in her life, and no one seems to care about it. Melinda can't find her voice to admit what really happened to her, just like the school can't decide on a "politically correct" mascot that will make everyone happy. Once Melinda does find her voice, the whole world opens up.
"IT happened. There is no avoiding it, no forgetting. No running away, or flying, or burying, or hiding. Andy Evans raped me in August when I was drunk and too young to know what was happening. It wasn't my fault. He hurt me. It wasn't my fault. And I am not going to let it kill me. I can grow."
By the time Melinda accepts what happened to her and speaks it, nothing else seems to matter. The ever changing mascots are symbolic of the changes Melinda has made in her life.