Students Release 72,000 Ladybugs at Maryland High School as Part of Senior Prank

— -- Here's one way to bug your teachers.

Seniors at Chopticon High School in Maryland left a mark on their school in more ways than one -- in 72,000 ways to be exact. A group decided their senior prank would be to release 72,000 ladybugs to freely roam the hallways, according to the St. Mary’s County’s Sheriff’s Office.

Five suspects wearing masks and hoodies forced open the school’s back door around 3:40 a.m. on May 20 and spread the ladybugs before leaving, authorities said. Police told ABC News that two others did not enter the school at the time, but instead waited in a car.

Of the seven people involved, four are juveniles being charged with fourth-degree burglary, property destruction under $1,000 and disruption of school activities. The three adult males will be charged by criminal summons, police said.

None of the students have been identified by name.

A group of students ordered the ladybugs online for about $100, according to senior Eric Maxey, who was not involved in the night of the prank. He said about 75 seniors pitched in money to help pay for the bugs.

“Everyone was obviously laughing the next morning because it was so unique,” said Maxey. “It didn’t cause any damage and the school had already bagged up most of them by our second period.”

Janitors from local schools came to help clean up the ladybugs and were armed with vacuums on their backs, said sophomore Trinity Alexander.

School officials decided one senior involved will not be allowed to walk at graduation this Wednesday. Students protested that decision this morning before their graduation practice, according to Alexander, who helped organize the protest.

Chopticon High School officials did not immediately respond to ABC News’ request for comment.

Maxey said 2015 marks "our school’s 50th graduating class and this was us leaving our mark in a memorable way."