Edwin Klemm is being held on a $600,000 bail and faces 11 counts of criminal sexual assault.
Klemm is said to be a popular teacher at Wheaton North High School. Now, he has a mug shot and arrest record, not what students expected.
"If you would ask anyone who was the top teachers, who was most popular, he would be on that list," said Jeff Harper. "I'm surprised at what happened."
Klemm is accused of initiating a sexual relationship with a student when she was 16. Klemm is charged with 11 counts of criminal sexual assault, and is suspended without pay.
Former students say Klemm was close to kids on the speech team, including the victim, who is now a college student. Authorities say sex occurred in classrooms, the school parking lot, and Klemm's home.
"To be perfectly honest I wasn't surprised since I had heard about the relationship he had with the student," said a former student who asked not to be identified. "He was actually quite open about it. He told people that the reason he was asked to leave the speech team was because he, supposedly, had too close of a relationship with her."
Members of the speech team left an awards dinner Wednesday evening, making no comments. But other parents and students say it's a sad case.
"I was pretty surprised to hear that it happened," said student Brad Klein.
"The man is innocent until proven guilty," said parent Kim Klein. "But you do the crime, you do the time."
Prosecutors say the relationship ended in November, 2011. They say the case unfolded when the parents of the victim found a love letter from Klemm.