Buchanan High School students were suspended Tuesday following a drinking incident after their prom Saturday night.
Clovis Unified School District officials did not confirm the number of students suspended Tuesday.
Clovis police said 38 students told them they had at least a sip of an alcoholic drink on their charter bus Saturday night.
Police said they received a call from the bus driver, who suspected that students were under the influence of alcohol after one of the students became ill on the bus.
The bus had stopped at the In-'N-Out Burger restaurant at Clovis and Herndon avenues after the prom.
The suspended students cannot return to school pending hearings scheduled next week.
"At issue for us is a report of illegal behavior on the way to and from a school activity," said district spokeswoman Kelly Avants.
"We make it very clear to kids, and it's talked about extensively about bad choices related to the prom. It's close to the end of the school year and there is a lot at stake, so it should not come as a surprise to anyone."
Laura Guzman Magill, a Fresno lawyer, said she has spoken with one parent about the drinking incident. Magill said she thinks suspensions exceed the school's jurisdiction.
Students, Magill said, also are being threatened with expulsion from Buchanan, which means they could end their high school careers at the district's continuation school. That would affect their college careers, she said.
She contends that the prom is not a school-sponsored event. But even if it is, first-time alcohol use is not cause for a student to miss school, Magill said.
Student athletes who have signed a pledge not to drink alcohol or use drugs can be suspended from the sports they play, but not from school, she said.