By Rebecca Harris When a group of New York prep school students were banned from attending their senior prom last month after getting high on a class trip, their parents were angry-some at the school administration more than at their kids, students say. Quick to lay down the law, one or several of those parents reportedly rented a yacht and, in an interesting display of discipline, threw the banished seniors an alternative, private prom party. About 15 seniors at the Ethical Culture Fieldston School admitted to consuming brownies containing marijuana on an overnight class trip April 29-30 to Camp Mason, a YMCA summer camp in New Jersey, according to two classmates who just completed their senior year at the Ethical Culture Fieldston School. The accused students were prohibited by administrators from attending May 19 color war festivities as well as the Fieldston senior prom at Studio 450 on May 29. Two sources spoke on the condition of anonymity, and several other Fieldston students confirmed that the "anti-prom" was held the same night as the official school party. "We had this field trip and some kids brought pot brownies to it. They couldn't prove it, I guess, but everyone knew," said a female student who graduated with the rest of her class-or "form," as it is called at Fieldston-June 6. On the same night as the scheduled prom, the banned seniors, their dates and some friends attended a party on a yacht. "One of the parents ordered a yacht for them," said a male student who just graduated. "I don't think any of them said no-it's a pretty cool alternative." One girl's parents were angry with her for getting in trouble with the school, but most of her classmates' parents "didn't seem to care that much," according to a source. Pictures and posts on Facebook and Twitter documented a night of revelry-or "yachtingtons" as dubbed by one photo album title-for the banned seniors, courtesy of their parents. Comments branded the event "Fieldston anti-prom 2012." In one photo posted on Facebook, a group of girls who had been involved in the drug incident posed together. It was captioned 'j sisters'-"like joint sisters," the female student said. She added that the picture has since been taken down. The Fieldston administration has made a concerted effort to prevent students from discussing the incident and school officials denied repeated requests for comment. Fieldston Upper, whose campus is located in the Riverdale area of the Bronx, includes students in ninth through 12th grade and is a member institution of the Ivy Preparatory School League, often considered the Ivy League of New York City private high schools. Fieldston is included in the League alongside schools such as Horace Mann, Trinity and Dalton. In 2011, Business Insider reported Fieldston as America's 11th most expensive private high school. Tuition and fees for the 2011-12 academic year totaled $37,825 per student. Fieldston also has two lower schools for pre-kindergarten through fifth grade: Ethical Culture, on the Upper West Side, and Fieldston Lower, on the Riverdale campus along with Fieldston Upper. Sixth through eighth graders attend Fieldston Middle, which is also located on the Riverdale campus. The four schools serve about 1,600 students in total, many of whom hail from the Upper East and Upper West sides. According to both students, Fieldston administrators threatened harsher disciplinary consequences in order to elicit confessions from the students accused of getting high on the Camp Mason overnight trip. They said the school claimed to have a list of "the kids we know who did it," and that the accused teens were told that if they confessed, they could avoid further disciplinary action-including potentially notifying the universities they will attend in the fall. "The administration said, 'If you come and confess, you won't be allowed to go to prom?but if you don't confess and we know you did it, we'll contact your schools and you may not be able to walk at graduation. And you still won't go to prom,'" the female student said. The other student criticized Fieldston officials for using "scare tactics" to compensate for what he desribed as a lack of evidence that the students were under the influence of marijuana. "They all confessed," he said, "but parents were angry at how [the school] gathered evidence. A lot of people thought they handled it badly." The female student disagreed with his criticism of how Fieldston officials handled the incident. "I think the school was more or less fair about it," she said. "[They said,] 'We're not gonna ruin your future, but there will be consequences if you go against our rules.'" The students' accounts are confirmed by an email sent to parents of the class of 2012 by Fieldston Upper Principal John Love on May 11, after most, but not all, of the students involved, had confessed. The email does not go into detail about the accusations-students eating marijuana brownies on a school trip-referring to the situation only as "a recent incident." "We feel it is absolutely essential to our mission and to the environment we want to create for our students that we take violations of this rule very seriously," read the email. "We asked that the students involved come forward and take responsibility for their involvement, telling them that if they did so they would lose the privilege of participating in the color war on Friday, May 18 and of attending the prom at Studio 450 on May 29. We also said that if a student was involved and chose not to come forward, his or her case might be brought to the Discipline Committee, with potentially severe consequences." No students other than those who came forward voluntarily were ultimately subjected to disciplinary action at Fieldston.