Parents could face enforcement actions if they leave their engines running outside school gates.
A new anti-idling scheme is being considered by Trafford Council following a report to its executive earlier this week.
The scheme would aim to cut down air pollution outside schools across the borough.
If approved, the council's enforcement firm 3GS, currently employed to fine people who litter and fly-tip, could enforce the new rules.
It is already illegal to leave engines running unnecessarily while the vehicle is stationary on a public road.
From spring this year, the council will be installing signs outside schools reminding drivers not to keep their engines running and will be working with schools to encourage healthier travel.
Trafford and the other boroughs in Greater Manchester are working to tackle air pollution and is developing a Greater Manchester Clean Air Plan.
Coun Stephen Adshead, executive member for environment said: “Because of air pollution, children’s health is particularly at risk because their lungs are still developing. Trafford Council is passionate about improving air quality and road safety at our schools and will do all we can to make sure our children are breathing clean air.
“We are taking a tiered approach with a number of steps to let drivers know that they should not be leaving their engines running when they are sitting in their cars outside schools.
"This is of vital importance to us and supports our corporate priorities of supporting children and young people, health and wellbeing and the environment.”
