Nearly two months after Cooper Union students let 2,100 ping pong balls cascade down the school’s four-story Grand Stair, a handful of those involved received a whacking long in the making.

A school judicial trial was held on Monday — at high noon, no less — for five students who were identified from images taken from surveillance cameras.

One was falsely identified from the camera, and dismissed. Two freshmen were given 60 hours of community service, and two juniors were given a 45-day probation that prohibits them from committing another infraction without receiving a harsher punishment.

When the trial was announced, Students for a Free Cooper Union, which had organized the ball drop as a protest against tuition charges, called foul on the selection of the five students to be tried. “There was a much larger pool of people involved,” said Victoria Sobel, a member of Students for a Free Cooper Union, who put the number closer to 30 to 50. “It’s possible they wanted to make an example of these students.”

Justin Harmon, Cooper Union’s vice president for communications, said that’s not the case, and that people involved in filing the complaint “developed what evidence they could based on the existing evidence.”

Free Cooper Union is also fighting changes to the school’s code of conduct that, it says, would make it easier to crack down on protests. The new version, per a draft, would forbid “deliberate or knowing disruption of the free flow of pedestrian traffic on Cooper Union premises” and “behavior that disturbs the peace, academic study or sleep of others on or off campus.”

Harmon said Cooper Union’s board of trustees wants more feedback on the draft. The dean’s office is currently working with students and faculty to get more information that is “as comprehensive as possible,” he said.

“The student and the faculty, and some administrators, have a lot of confidence in the way that Cooper is structured now,” said Sobel. “The new code completely changes how the school has functioned over the last 150 years.”