Arryn Tyler says she stood up and protested the principal's decision.
"I stood up. It was wrong of me. I gave her the middle finger," she said. "I was very mad at the time."
Tyler says she then walked to the front of the auditorium and had words with the principal.
As Tyler turned to leave, she says, she was grabbed from behind. Tyler says she didn't know it was a sheriff's deputy.
Authorities say Tyler kicked the school resource officer, who then fell on her, causing her to scrap her head and knee.
"He lifted me up from the ground, so I was kicking my feet. Next thing I know, I am going face first - like my face was slammed into the ground and a huge weight on top of me," Tyler said. "His belly on my back, he was on top of me."
Tyler says she was handcuffed then dragged out of the auditorium.
According to authorities, an ambulance crew was called and she was taken to the hospital for a checkup, then released.
The sheriff's office charged Tyler with resisting arrest, assaulting a law enforcement officer, and disorderly conduct.
Tyler calls the deputy's actions excessive. The entire incident, she says, has taken the spirit of their homecoming from a lot of her classmates.
The school principal had no comment about the incident.