An Illinois judge set the bond at $40,000 for an algebra teacher at a Christian school who admitted to investigators that he masturbated behind a lectern Friday during class, WWLS-TV reported Wednesday.

Paul LaDuke, a 75-year-old minister in charge of a class full of minors, confessed that until one of them caught him in the act, he would put an apron on and masturbate while he thought about girls in the room for 10 years.

LaDuke was fired from Schaumburg Christian School that afternoon, but administrator Jim Toth said he was likeable.

He has been a teacher here for 27 years, never had issues like this in the past that we were ever made aware of, he said of LaDuke, now facing a charge of sexual exploitation of a minor. Many students are very saddened that this has happened.

LaDuke's attorney Irv Seidler said his client's age might explain how he behaved.

He has some evidence of dementia, WBBM-AM quoted him as saying. He has limited recall of what happened.

Although she was the first student who said anything about LaDuke masturbating, Sgt. John Nebel said, the girl who was upset enough to report him to one of the other teachers is fine, as are her 12 classmates.

Obviously, she was distressed and upset by what occurred, but we're very thankful that she brought it forward, said Nebel.

What makes his actions more perplexing, his cousin Larry LaDuke told the Chicago Tribune, is that he's a man of the cloth.

He's always followed his faith, he said. I can't believe this is happening.