COLORADO SPRINGS, Colo. – A former Colorado high school teacher was sentenced to at least eight years in prison, with the potential for a life sentence, after he “cup checked” several male students and goaded them about their sexuality.

Lee Edward Riddle, a 30-year-old former German teacher at Colorado Springs’ Widefield High School, was convicted Aug. 20 of five counts of sex assault on a child by a person of trust. On Monday, Judge Thomas Kennedy sentenced Riddle to an indeterminate sentence with an eight-year minimum, which means he could remain in prison for life, The Colorado Springs Gazette reports.

Kennedy noted that Riddle’s behavior with students was “more than just horseplay” at his sentencing.

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“You crossed those boundaries repeatedly,” Kennedy said, according to the news site.

Riddle’s arrest affidavit, posted on the Denver Westward blog, states that a 17-year-old student told the El Paso County Sheriff’s Office Riddle grabbed his nipple in class, called him ‘Cutie,’ and made other inappropriate sexual comments.

“(The victim) explained one incident where he and another student … were comparing shoes and shoe sizes. During their conversation Mr. Riddle walked up and inserted himself into the conversation saying to the boys I am 12 inches,” according to the affidavit.

In another conversation, Riddle asked a student if he was bisexual.

Police also followed up with other male students whose nipples were pinched and others who the teacher “cup checked” – or whacked in the genitals with the back of his hand.

More male students interviewed by police said Riddle flirted with them, and engaged in multiple conversations about gay sex. One student “explained one conversation was Mr. Riddle telling him that it hurts the first time but it gets better and the guy on the bottom receives while the guy on top gives.

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“He stated Mr. Riddle has touched the inside of his upper thigh and has rubbed the top of his shoulders while in class,” according the affidavit.

Police also learned that Riddle had declared to school officials that he was a homosexual, and “all of the students we spoke to stated it was obvious and common knowledge that Mr. Riddle is homosexual,” the affidavit reads.

The mothers of two of Riddle’s victims spoke to the court during his recent sentencing.

“One mother said she knows the community has seen more horrific crimes, but the court should make an example out of Riddle to deter future offenders. She struggles with not having protected her child and instead telling him to respect his teachers …” the Gazette reports.

The other mother said she’s lost her trust in the school system.

Riddle’s mother and two friends also spoke, and pleaded with the judge to issue the minimum mandatory sentence, according to the news site.

“I hope to God you won’t put him in prison,” Riddle’s mother, Kathy, told the court. “It will kill his spirit. He is the sweetest person I know. He doesn’t do anything but think of others.”

Judge Kennedy did issue the minimum sentence, but noted that Riddle likely caused severe damage to students at a time they are exploring their own sexuality.

“If Riddle had demonstrated the same behavior with female students, there would have been no doubt about his intent, Kennedy said,” according to the Gazette.