Classes in the Roslyn School District start Thursday, but before they do the high school principal is telling some students their behavior is putting schools at risk.

According to a letter from principal Scott Andrews, his office was inundated with calls, emails and pictures of a party that happened last weekend that was attended mostly by high school seniors.

A copy of the letter, which was sent out Monday, was obtained by News 12. The letter says more than 100 students were partying at a home, and pictures depict them in large groups, not wearing masks and sharing drinks.

Andrews called the students' actions thoughtless, devastating and disrespectful.

While no one in Roslyn was willing to go on camera to talk about the letter or party, some people who spoke off-camera say the party was held outside and some wore masks.

Nassau Executive Laura Curran says social distancing, wearing masks and frequent cleaning are some of the reasons for the county's low infection rate.

"We can't afford to go back, also kids need to get back to school, we can't jeopardize that either, it's really important that we continue using these common sense protocols so we can get back to some kind of normal," says Curran.

Personal responsibility for students and parents is something the principal wrote about frequently, saying, "The way you conduct yourself in the world directly impacts others. The way you parent your child directly impacts our schools."

He also goes on to say if a percentage of the community chooses not to practice social distancing protocols, all parents should expect school closings to become an inevitability.

News 12 reached out to the Roslyn superintendent and a spokesperson says she has nothing more to add and referred to the letter.