For the first time, this year the Martha's Vineyard Regional High School junior prom will require not just a ticket to enter, but a green light from a breathalyzer.

After alcohol use caused problems at last year's prom, high school principal Margaret (Peg) Regan considered cancelling this year's prom and revisiting the issue the next year, but at the students' request, Mrs. Regan instead collaborated with juniors to make prom safer.

But breathalyzers were not the students' first choice.

"At first there were a lot of grumblings," said class advisor and guidance councilor John Fiorito, who planned the prom this year with students and will be chaperoning for the eighth consecutive year.

Some students felt they were being punished for the mistakes of the previous class.

"I agree that since last year they should take some precautions, but it seems like they're taking last year out on us," said junior Maureen Fitzpatrick, who is also on the prom committee. "I think combined with all the other rules, it's a bit much."

The prom will be held tomorrow night at the Outerland nightclub near the airport.

Students will not be the only ones subject to scrutiny. Chaperones will also be required to take a breathalyzer test, which some find frustrating. "It would be nice to have a glass of wine with dinner," said one chaperone who asked to not be named.

But some students said the extra requirement is an admirable attempt at fairness and setting a good example.

"It's the way it should be. It shouldn't be just the kids," said junior Marguerite Cogliano, who is head of the prom committee. "They want to show us that ‘We can do it and we're allowed to drink.' "

Other rules include a deadline of 8 p.m. to enter prom, which is not new, and a no-reentry policy, which is stricter than last year's police escorts to and from vehicles for forgotten items.

Some students said they think using breathalyzers is reasonable.

"Last year there were a lot of kids that were drinking, so now we don't have to worry about it," said junior Brittany Stone, who thought there was a good chance students would be drinking before this year's prom too. "I think it's kind of a good idea," she said.

School administrators said this week that they felt breathalyzers were the only acceptable solution. Both Mrs. Regan and Mr. Fiorito have spent time discussing the issue with students. Police will not be involved if the readings are amber or red, indicating alcohol consumption.

"Our message to kids is, you don't have to drink to celebrate" said Mr. Fiorito. "We're not trying to expel you, we're not trying to arrest you." Mr. Fiorito said he was hesitant to embrace the use of breathalyzers, which has been a back-burner topic at administrative meetings for years.

"I've always been torn on the notion because the majority of kids make good decisions . . . but I've come full circle," Mr. Fiorito said. "It can be at least alcohol free and that's our personal responsibility as a school."

Students who do not pass the breathalyzer test will be required to have a parent pick them up. Prom chaperones have the telephone numbers of parents from contracts that were signed by parents and students, agreeing to the prom's no alcohol policy and use of breathalyzers. Mr. Fiorito said no parents have complained to the school about the new policy, but students are a different matter.

"Students are mad about it," Ms. Cogliano said. "But it's four hours of your life. It's not like bags are being searched or you're being patted down either. Once you're in, it's basically trust. In that respect they're being somewhat generous."

Based on ticket sales - all 300 tickets are expected to be sold by tomorrow night, which would fill the Outerland to capacity - the new policy has not affected prom attendance, although that was an initial concern. "I thought, ‘It's going to be 50 kids,' " Ms. Cogliano said, recalling her reaction when she first heard about the breathalyzers. Now she has a different view." As much as kids complain, you know they're going to come and have a good time," she said.

Some students speculated that the breathalyzers will be viewed as a challenge to beat, possibly by using drugs that administrators are not screening for, or by sneaking alcohol into the prom. Others said they believe the stricter rules could lead to more drinking later on.

"It will probably be a crazy night because kids can't drink at the prom," said David Holmberg, a senior who is co-president of SafeRides, a student-run program that provides rides home for high school students, no questions asked, through the use of a hotline. SafeRides has extended its hours to 3 a.m. instead of 1 a.m. tomorrow night, and if there is a backup of calls, the driver will work late. Mr. Holmberg will be the driver on prom night. "Two years ago we were out until four or five in the morning, so we're expecting to be out pretty late," he said.

On the other hand, some students may just be too tired to party. Prom is the same day as SATs this year. But according to juniors, it could be worse. "At least they're not the day after the prom," Ms. Fitzpatrick said.