Lenny Boberg and his mother, Mindy Boberg, were approached Thursday immediately after the performance by St. Stanislaus Principal Pal Bowlin, who Mindy Boberg said told her the move constituted gross misconduct, the Winona Daily News reported Saturday.
Boberg said her son had performed similar Michael Jackson routines the past two years at the event, and the performance had been approved by school officials at a Tuesday rehearsal.
She said she didn't know why her son was singled out when some students performed wearing boxer shorts and others shook their "tail feathers."
Bowlin sent an e-mail to Winona Area Catholic Schools faculty, staff and families regarding the incident.
"On behalf of the Winona Area Catholic Schools, I would like to thank all the students, teachers, parents, and friends of our school for your support of our Lip Sync contest. So many people worked incredibly hard to make it a great event. We did have one act that was clearly inappropriate. I want to extend my apology for that situation," the e-mail read.
He said he plans to meet with the Bobergs Monday to discuss the suspension.