The education minister says pupils should confront parents who leave their car engines running outside the school gates.
Damian Hinds told The Times that motorists who leave their engines on are damaging the health of children with the exhaust fumes.
He urged schools to challenge parents who engage in the practice and said councils should issue spot fines to those who don’t turn off their car’s ignition.
Mr Hinds cited the example of Thomson House Primary School in Mortlake, west London, which has told parents not to drive to and from the school premises.
Pupils at the school have recently started carrying out patrols outside the school gates.
Writing in The Times, Mr Hinds said he wanted to see “more schools following the example of Thomson House… where children confront parents outside the school gates who persist in leaving their engines running”.
The Department for Transport says it is considering raising fines for engine idling from £20 to £100.
Mr Hinds wrote: “Government air quality data shows levels of pollution in urban areas are much higher during rush hour than at any other time of day, and it troubles me that children are being exposed to this daily on the school run.
“Exhaust fumes are not only bad for the environment, they’re also very bad for us too.
“Plenty of people will let a car idle unnecessarily while waiting for someone or something. It won’t make the time pass any quicker if you turn your engine off but it will make a huge difference to the air supply.”
Although Mr Hinds said he accepted some parents had no choice but to drive their children to school because of a lack of public transport, he added: “To them I would say this: please turn off your engine if you are waiting for your kids outside school.”
He said: “If we want children to spend more time outdoors instead of sitting inside looking at screens then we have to make sure we are not swapping one unhealthy practice for another that’s potentially even worse.”