The students were suspended and face charges after officials say they released chickens in their New Jersey high school.
A janitor found the birds before Woodbridge High School opened last month.
Eighteen-year-old Bryan Peter, two 17 year olds and a fourth student were suspended for five days. They'll also lose "senior privileges," which include attending the senior prom and walking during graduation.
Woodbridge Police Lt. Carl Lizzano told The Home News Tribune of East Brunswick they're charged with a disorderly persons offense and trespassing.
The minors would likely face no more than community service, according to police.
The students and their parents told the newspaper officials overreacted to the joke.
Principal Arthur Warren says he doesn't want the school day disrupted.
Fan, follow and download: Get the latest from NBCPhiladelphia.com anytime, anywhere. Follow us on Twitter, Facebook and NBC Philadelphia. Sign up for our breaking news newsletter. And, get breaking news delivered right to your mobile phone -- just text PHIBREAKING to 639710 to sign up. (Message and data rates may apply.)