Sixth grade students are now attending classes at Norwood Avenue Elementary School, seventh grade students at East Northport Middle School, and eighth graders at Northport High School.
The students did not have classes Tuesday or Wednesday as officials planned for the transition.
Maria Monda's twin eighth graders are now attending the high school.
"They're just looking forward to being in a place where they feel safe," she told Eyewitness News reporter Kristin Thorne.
Monda applauded school district officials for how well they planned for the transition of the students.
"As soon as the building was announced it was closed, they emailed and they've been keeping us up to date on everything," she said.
Students were welcomed to the schools Thursday with signs and balloons. High school students wrote letters to each eighth grader with words of support and tips on how to navigate the much larger school building.
"Everybody has just been working together to make it happen," Monda said.
Last week, Northport-East Northport school district officials closed Northport Middle School for the remainder of the school year after benzene was detected in soil samples from two septic systems outside the building.
Benzene is a potentially dangerous chemical, which according to the Centers for Disease Control can cause headaches, confusion and even cancer if someone is exposed to high levels of the chemical for an extended period of time.
In a letter to parents, Superintendent Robert Banzer said preliminary air testing did not detect benzene or any other harmful airborne chemical inside the building or from the soil samples or at the source of the septic tanks.
"However, in the best interest of our students and staff and in consideration of ongoing testing and remediation, the building will be closed for the balance of the school year," he wrote.
Eyewitness News has been reporting since 2017 on health complaints from parents and students at Northport Middle School. Students and teachers have reported suffering from migraines, nausea, confusion and mental health issues.
At one point, school district officials discovered petroleum based products including asphalt adhesives and roofing tars were being stored beneath the classrooms. The wing of the school was closed down while the products were removed. However, environmental testing continued.
An Eyewitness News investigation found that health complaints stemmed back to 2000, when more than a dozen health and safety incident reports from teachers and students documented complaints of strong odors, difficulty breathing, headaches, itchy eyes and chest pains.
Concerns about toxins and pollution resurfaced in 2011 with another health and safety incident report describing similar ailments to those experienced by teachers and students in 2000 and describing smells that made people "feel dizzy and sick."
Laura O'Donohoe's son was in sixth grade at the middle school and is now attending Norwood Avenue School. She said she feels better that he is no longer in the middle school building.
"I always err on the side of caution," she said.
Parents spoke out to the school board at a regularly scheduled school board meeting Thursday night. It was moved to the high school to accommodate the crowds that are expected.
Even parents who disagreed about the solution did agree about how hard the teachers and administrators worked to carry it out.
At the meeting, parents heard from a representative of a lab hired by the board who said his preliminary testing inside the school showed no dangerous toxins, leading some to ask why the school decided to take such drastic steps.
But even those who supported the move were upset about how long it took to make the decision.
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