When at first your protest doesn’t succeed, try it again in East Hampton.

That’s the lesson parents at a top public school on the Lower East Side are putting to the test today.

A busload of families from New Explorations in Science, Technology and Math, a school for gifted children better known as Nest+m, plan to picket at the Ross School’s leafy campus in East Hampton today to plead with that school’s parents to oppose the opening of a charter school in the Nest+m building.

The city has said it wants to place the Ross Academy Charter School in Nest+m’s facility on Columbia Street. The charter, to open with 160 students, will be modeled on the private Ross School, which was founded by Courtney Sale Ross, the widow of a Time Warner chairman, Steven Ross.

Parents of Nest+m students oppose the plan, claiming it will put the squeeze on much-needed classroom space. Earlier this month, hundreds of families picketed on the steps of City Hall. The Department of Education says there are enough seats for both schools.

“We’re going out to the Hamptons because that’s where the Ross School is, and we’re going to try to appeal to the parents and appeal to Courtney Ross not to put the charter school into Nest’s building,” the vice president of the PTA, Emily Armstrong, said.

Parents have painted signs with slogans such as “Save our success” and “Please help us.” Some families said they would return from their spring break vacations to participate.

“We’re not going to be insulting or anything, but we’re hoping to speak to some parents,” Ms. Armstrong said. “We’re parents and we want to reach out to parents.”

They planned to board a bus at 4 a.m. this morning to make it to Long Island in time to greet parents dropping off their children at school.

“The Nest community is taking their protest to the wrong place,” a spokeswoman for Ms. Ross, Diana Aceti, said. She said Ms. Ross did not request space in the Nest+m building, although she did request a Lower East Side location because of the charter’s collaboration with NYU’s Steinhardt School of Education.

Last year, Ms. Ross toured the Nest+m buildings when she and NYU representatives visited several city schools with different educational models.

“Ross had absolutely no idea that months later the Department of Education would request that Ross Global Academy be located in the building at 111 Columbia St.,” Ms. Aceti said.

Enrollment at Nest+m is now at about 730 students, or half of the education department’s calculation of its capacity. The principal, Celenia Chevere, says she has accepted another 400 students for September and will have to turn children away if the charter school opens. The city disputes that figure and has asked the city’s special investigator for schools to investigate Ms. Chevere, claiming that she has tried to make her school appear at capacity when it is not.

Another successful public school, P.S. 154 in Harlem, is also protesting the city’s plan to move a charter school into its building.

The flare-up at Nest+m has captured headlines in recent weeks because it highlights the struggle over classroom space as the Bloomberg administration opens more small schools. It also touches on issues of class and race.

Nest+M is more than 50% white and puts students through a rigorous admissions process, while the city’s charter schools are overwhelmingly black and Hispanic and accept children based on a lottery system.

Most of the 13 charter schools slated to open in the fall will share space with at least one other school. Charters are independently run public schools that operate outside the normal public school system. The city’s schools chancellor, Joel Klein, considers them essential to his systemwide overhaul.