"He's just a great guy. I know the girl that's being accused of it. She's a good girl too. It's a bummer for him and it's a bummer for all the kids that loved him. He was a great teacher," said Simmonds.
The 25-year-old teacher is accused of having sex with an underage girl, one of his former students, who authorities say still attends Capistrano Valley High.
Authorities won't say exactly how old the alleged victim is as it might identify her. They'll only say she is between 14 and 17 years old.
Authorities say the alleged crime took place in Westbrook's former home in San Clemente.
School officials found out after receiving an e-mail from a parent over the Thanksgiving holiday.
"When we have credible information we will quickly and expeditiously conduct an investigation and we will do all we can to get to the truth of the matter to reassure parents that students are safe at school," said Capistrano Valley High School Principal Deni Christensen.
Authorities say Westbrook taught social science and world history. He also helped coach the school's surf team and girls volleyball team.
Authorities are calling for more possible victims to come forward.
"There is a possibility that there are additional victims because the suspect has been employed by this high school for the past three years," said Orange County Sheriff's Department Spokesman Jim Amormino.
"It's hard to believe. I can't believe -- I don't want to believe it actually happened," said high school junior Rachelle Moniak.
"It's ridiculous. He's my favorite teacher. I actually have a good grade in his class. He has a good way of teaching," said high-school junior Brenda Rodriguez.
Westbrook was placed on administrative leave Monday. He's also out of jail after posting $50,000 bail.
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