The scheme was born when Royal School, a fee-paying primary school in north London, applied to Camden council to increase its roll from 120 to 153 in 1995.
Councillors were concerned at worsening pollution outside schools and would only accept Royal's planned increase if the number of cars coming into school was cut by 30 per cent over three years.
Parents worked with the school to come up with school runs that would enable one car to pick up several children.
A spokesman for the council said: "Home post codes of students identified clusters of addresses. The carrying capacity of the car was not considered because we think that smaller cars are more environmentally friendly."
Mark Gilks, the council's director of environment, said that some schools had five times the level of expected pollution outside their gates. But the results of the Royal experiment have exceeded the council's expectations. In just 12 months, the level of traffic into the school has been reduced by 23 per cent. Today councillors will vote on a package of measures - including extending the scheme to other schools.Reuse content