There were as many as 80 students involved in the incident, but so far the principal says 25 have been identified and are paying a high price.
Heritage High School senior Marco Sanchez says he was among 80 seniors who participated in a prank that administrators says crossed the line from harmless fun to serious vandalism.
"We didn't think it was too harmful, you know, with washable paint; we knew we'd get in a little bit a trouble, we didn't think we'd get suspended for five days and not walk," Sanchez said. By "not walk," he means not participate in Saturday's graduation ceremony.
Sanchez provided ABC7 News pictures showing the seniors' antics last Thursday night. Students can be seen painting on the ground of the school's quad. A small group took it step further, by chaining up a lamb and leaving it in the campus quad overnight.
Principal Larry Oshodi says he's identified about 25 of the students who participated. Many received five-day suspensions, which means they cannot take this week's final exams. For some of them, that could jeopardize their graduation and potentially college acceptances.
"Consequences have been assigned to those have been identified as being involved," Oshodi said.
Others think the consequence of having to clean up after themselves over the weekend was enough.
"The punishment doesn't fit the crime," senior Jasper Dhariwal said. "They spread washable paint on the ground, and they even offered to clean it up and they did."
"Yeah, they destroyed the school, but I still think they should be able to graduate and walk and stuff," student Nick Rovira said.
"That's really tough for me; as a parent, I can't imagine my kid going all year and then making a mistake at the end," parent Kathaleen Baisch said.
"They're harmless kids, they're harmless, they're not going to hurt nobody; you know, I just think they were trying to have fun," parent Carol Stai said.
To add insult to injury, Sunday night, members of another former class came apparently and sprayed paint all over the windows, a second incident in less than five days. That was cleaned up by the end of the school day.
As for the students who've been suspended over last week's incident, many of their parents are meeting with the principal Tuesday afternoon.