Nearly two thirds of teachers would support car-free roads outside schools during drop-off and pick-up times, a survey suggests.
The poll also indicates that more than half (59%) want the Government to take urgent action to improve air quality outside schools.
A survey of 840 people in teaching roles across the UK found that 63% would support a ban on motor vehicles outside the school gates at the start and end of the day.
When asked what would help reduce the levels of air pollution outside schools, 34% said encouraging more people to walk, scoot and cycle would help reduce toxic fumes.
Some 28% said educating the school community would help, and 26% cited school road closures.
The majority (59%) said a lack of alternative routes for traffic was one of the main barriers to closing the road, the survey for walking and cycling charity, Sustrans, found.
One in three teachers are worried about air pollution, with 43% saying idling car engines outside school gates cause concern, while a further 63% cited it is a concern because the school is based on or near a busy main road.
The survey comes after a report from Public Health England (PHE) called for a raft of measures, including stopping cars idling near school gates, promoting car pool lanes, and providing priority parking for electric cars.
Published earlier this month, the report said air pollution is the biggest environmental threat to health in the UK, with between 28,000 and 36,000 deaths a year attributed to long-term exposure
Sustrans CEO Xavier Brice said: "We need to radically change the way we travel.
"Idling car engines and snarled up roads poison the air and our children's bodies across the UK.
"For too long now, dangerous levels of air pollution near schools have been ignored. Finally this is starting to change.
"Our survey makes it clear that teachers want urgent action to clean up toxic fumes.
"They see closing the roads outside their school as an effective solution but need support
The teachers' survey has been released to launch the Big Pedal 2019 - a competition to encourage more young people to cycle, walk and scoot to school.
Held annually by Sustrans, more than 2,200 school have signed up to take part in this year's challenge, which runs to April 5,
This year also sees, for the first time, 40 schools across England, Wales and Scotland, closing their streets to motor vehicles for one day.
Radio and television presenter Angellica Bell, who launched the Big Pedal at St Richard Reynolds Catholic College in Twickenham, said: "I know first-hand the joys and benefits of riding a bike and how important it is for children to be active from an early age and that's why I support the call for creating a safer and calmer environment around schools for children to cycle and walk."
Sophie Gallois, Unicef UK's director of advocacy and communications, said: "Every day, one in three children in the UK is breathing in harmful levels of air pollution that could damage their health and impact their future.
"Worryingly, children are most exposed to toxic air on the school run and while at school, so a ban on motor vehicles outside the schools gates has potential to make a real difference.
"Reducing children's exposure to air pollution is not just about the school street itself, but also taking quieter routes to school, away from busy main roads.
"The Government must take urgent action to tackle this growing health crisis by putting children's health at the heart of its work on air pollution."
A Government spokeswoman said: "We are committed to driving down emissions across all modes of transport, and recognise that greener travel options are a crucial way to clean up our air.
"Just last week we announced a £23 million investment to rejuvenate cycling and walking across the UK, on top of the £2 billion we are investing over the course of this Parliament."