News of the arrest spread quickly around campus Friday.
"I was getting ready to leave for school and I just checked my Facebook real quick, and there it was. It was all over the place and everyone was talking about it already," said student James Olafsen.
Investigators said the sexual encounter occurred over the summer break. They were made aware of the matter Thursday when a student told a school resource officer, prompting an investigation.
"When they found the allegations to be true, they immediately went and arrested Mr. Hill," said Riverside County Sheriff's Department Cpl. Courtney Donowho.
School officials said Hill was a substitute teacher at the high school off and on for two years.
"I know a lot of people don't like him because he is not very friendly with anybody," said student Taylor Campbell.
Parents who picked up their children from the school Friday said this is not something any student should have to face.
"I am very concerned about that, that is not safe and children should go to school and be safe. They should feel safe when they go to school," said parent Julie Marquez.
Hill is out on bail and is on unpaid administrative leave pending the outcome of the investigation.
Authorities are continuing the investigation and the Lake Elsinore Sheriff's Station is asking the public for help. Anyone with information should contact the Lake Elsinore Sheriff's Station at (951) 245-3300.