Pupils living near a legal red light district have been propositioned for sex and their head teacher said he feared one of them could be abducted.
The Managed Approach (MA) area in Holbeck, Leeds, allows sex workers to operate without fear of prosecution.
One girl said she was asked for sex as she walked through the zone to school and head teacher Ben Mallinson said he was worried pupils could be harmed.
Leeds council urged anyone with concerns to get in touch.
Many students from The Ruth Gorse Academy have to walk through the managed red light district to get to school.
They said it was a daily occurrence to see sex workers, used condoms and discarded needles lying around and felt at risk.
One pupil who was propositioned said a man approached her and asked if she was "open for business".
"I was 13 and was wearing my school uniform walking to school. I barely got down the street and I was approached by a man asking if I was a prostitute," she said.
"I've been asked by sex workers if I was one of them as well walking back from school on a different occasion.
"It will happen to other children probably just as it happened to me and as long as the zone is there it will carry on happening."
What is the managed red light zone?
Dubbed Britain's first legal red light zone, the "managed approach" to street sex work in Holbeck has been the subject of considerable debate since it began in 2014.
It was set up to try to control the trade and has allowed street sex workers to operate freely without fear of arrest between the hours of 20:00 and 06:00.
Local residents have held protests in the past, claiming the area was plagued by anti-social behaviour.
Rules of the managed area have included no littering of condoms, a ban on drug use and that people should respect business and other properties.
The Safer Leeds Partnership has stated crime, public disorder and anti-social behaviour would not be tolerated.
An independent review in July 2020 found the community should have more of a say on how it was run, relying less on police.
Another teenage boy said his friend had been asked for sex and another girl described how she had been followed and grabbed by a man.
She said: "I was really scared because I was by myself and it was dark. He was just saying 'I like you' and I was walking faster and he started walking faster."
The pupils' head teacher Mr Mallinson said he had also walked through the area and was "gravely concerned".
"There was extensive evidence of drugs and alcohol misuse, and experiencing that every day takes its toll on a young person's mental health and wellbeing," he said.
"Students should be free from harm and be able to travel to and from school without being worried for their own safety and that of their peers."
He has called for the zone to be scrapped and said if it continued, he feared a student could be abducted.
Leeds City Council's deputy leader Debra Coupar said safeguarding was its highest priority.
"I would urge anyone who witnesses any form of indecency or unacceptable behaviour to please contact the police or Safer Leeds partnership immediately so a full and thorough investigation can be undertaken," she said.
"Along with the police, a designated Safer Leeds team also patrols the area of the Managed Approach and we will always take appropriate and firm action against any individuals involved in unacceptable behaviour.
"No incidents that are reported will ever be ignored."