NASHUA – A former Alvirne High School coach and paraprofessional pleaded guilty Friday to charges that he paddled several students for sexual gratification and was sentenced to three years in jail. Michael Palmer, 32, of Wichita, Texas, had been jailed since his arrest in June, and he had faced 120 misdemeanor sexual assault charges, alleging assaults on three boys in 2008.

Hillsborough County Attorney Robert Walsh agreed to drop most of the charges after Palmer pleaded guilty to nine counts of sexual assault, simple assault and criminal threatening on Friday in Nashua District Court, court records show.

Judge Michael Ryan sentenced Palmer to three consecutive 12-month terms in jail, with another two consecutive 12-month terms to remain suspended for five years after he gets out.

Palmer will be required to be evaluated, treated and register for life as a sex offender as part of his sentence, and so long as he remains on probation, he may have no contact with minors, and his computer use can be monitored, according to court records.

Most of the assaults took place in the teens’ homes, and others at Palmer’s former apartment at 40 Bowery St., Nashua.

Palmer formerly worked as a paraprofessional at Alvirne High School and coached the boys’ soccer and wrestling teams before resigning May 5, 2009.

Palmer admitted to abusing his position as an authority figure to spank three teens with either a belt, a paddle or his bare hand as “punishment” for misbehavior or bad grades, and forcing another boy to sit on his lap, and slapping the boy’s face. All four victims were Alvirne students at the time of the assaults.

Police began investigating Palmer in 2008, after someone stole his laptop computer and turned it over to police, suspecting it contained child pornography. Police searched the computer and found pornographic images of older men spanking or paddling teenage boys, but the images proved to be legal pornography, not child porn, police said.

Detective Steve Sweeney spoke with Palmer, who admitted that he was attracted to younger men, but added that “he was sensitive to the fact that his desires could pose a problem, being that he is a high school coach for boys,” police said.

Palmer told police he stays out of the boys locker room and holds all meetings in public view, to avoid any potential problem.

Police renewed their investigation the following spring, however, when a student disclosed to his mother that Palmer had been repeatedly abusing him, police said. The mother had questioned her son about text messages from Palmer on the boy’s phone, police said.

Palmer later admitted to police that he had been playing out scenes from his pornographic movies with the students and that he was receiving mental health help, police said after his arrest.