The student identified as Dylan was detained at a courthouse last week after a judge dismissed his asylum case.
A rally in support of Dylan and to demand his release is planned for Thursday outside Tweed Courthouse.
School officials try to reassure families that city schools remain safe spaces.
It's suddenly a no-win question faced by many undocumented immigrants.
Fail to show up for a scheduled immigration court hearing and face detention or show up for a scheduled hearing and have federal agents waiting to take you into custody.
"Going to the hearing is something we had been directing families to do and asking them but now with the courts fighting against human decency, we don't know what's going to happen," Naveed Hasan, with Panel for Education Policy, said.
Naveed Hasan is an immigrant, the parent of two public school students and a Department of Education board member.
He is speaking out after last week's arrest of a 20-year-old high school student from Venezuela.
ICE agents took Dylan into custody outside Federal Plaza in Manhattan immediately after a judge dismissed his case.
Dylan is the first known city public school student detained by immigration officials.
"Dylan had legal status. And he was sort of deceived into dismissing the deportation proceedings which also dismissed his asylum claim and at that point in time you don't have any status," Hasan said.
Dylan's family asked reporters to withhold his last name out of fear of retaliation from the federal government.
The 20-year-old attends Ellis Preparatory Academy, one of a half-dozen schools at the Kennedy Campus in the Bronx.
The school serves older immigrants learning English.
Amanda Hambrick Ashcraft is a parent advocate and member of the community education council, said, "We do not agree with this strategy, we do not agree with fear-mongering and division and hate tactics and scarcity mind-sets is how we are going to get through this and we will get through it together."
In a statement, the Department of Homeland Security said Dylan entered the country illegally and added, "If individuals have a valid credible fear claim, they will continue in immigration proceedings, but if no valid claim is found, aliens will be subject to a swift deportation."
Immigration advocates hoping for assistance from city hall should look elsewhere.
On Tuesday, Mayor Eric Adams made his position crystal clear.
"We have to be extremely careful because the New York City Council laws are limited on what coordination I can do. Sometimes it's a blessing and it's a curse," Adams said.
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