A growing number of parents, teachers and city lawmakers are demanding that the New York City school system reverse its longtime ban on students' cell phones inside school buildings.

So far, the mayor and the schools chancellor aren't heeding the calls.

On Friday, a handful of City Council members and parent activists announced a series of upcoming events aimed at pressuring the education department to change the policy.

City Councilwoman Letitia James said she's introducing a resolution to stop schools from confiscating cell phones, which she said were vital lifelines for parents and their children.

James and parent leaders say they don't object to rules requiring students to turn off their phones during classes, but they want the children to have access to them in emergencies.

"Quite simply, this is a safety issue," James said. "It's a safety issue that we have to resolve."

School officials say they're skeptical that they can count on students to keep the phones off. They also say phone can be used for nefarious purposes — cheating on tests, or taking inappropriate pictures in locker rooms, for instance.

Schools Chancellor Joel Klein told the Daily News on Thursday that possible solutions he's considered, such as special storage lockers, seemed too costly or unworkable. On Friday, Mayor Michael Bloomberg said he wasn't changing his mind.

"We don't need to have kids go off and look at entertainment and do other things during the classroom," Bloomberg said on his weekly radio show. "And we just don't have the ability to check the phones at the door. So I don't have any easy solutions for parents who want their children to have cell phones before school and after school."

The school system's ban — which opponents say has been only sporadically enforced — traces back to a 1988 policy that prohibits beepers and other communication devices. It has been interpreted to apply to cell phones and other gadgets, including iPods. Both cell phones and iPods are prime targets of theft in schools.

What thrust the cell phone issue into the public sphere recently was the system's decision to send portable metal detectors to random schools on a surprise basis in an effort to lower already falling crime rates. The searches have netted many cell phones.

Parents passionate about the subject invoke memories of major city emergencies, including the Sept. 11 attacks, as proof that cell phones are critical lifelines. Some also frame the issue as a civil rights matter.

"We talk about schools as prisons in this city," said Cecilia Blewer, a parent of two. "They're being acculturated to accept prison conditions. What I want to know is how they're teaching civics with a straight face any more. How would they explain the arbitrary searches and invasion of privacy?"

Several parent organizations, backed by the teachers union president and executive board, have called for some sort of compromise on the policy. The city's public advocate, Betsy Gotbaum, also has urged the mayor and the education department to develop a new policy.

During the Friday press conference, Carmen Colon, president of the Association of New York City Education Councils, showed off a thick petition with some 2,000 signatures of people who wanted a new policy.

For some students, it's an issue of fairness.

"The teachers still use their cell phones and the kids can't," said 15-year-old Ellia Munoz, a ninth-grader in Manhattan. "They don't have to take the cell phones. They can just see them get turned off."