* Each child makes around 4,000 journeys to and from school in the course of his or her education
* In 1971, 80 per cent of seven and eight-year-olds made their own way to school. Now it is under 10 per cent
* More than a third of children are driven to school by parents - double the figure of 20 years ago
* Most car journeys to school are less than two miles. Short trips cause a disproportionate amount of pollution because catalytic converters take time to warm up
* One in five cars in the morning rush hour is transporting children - parents ditching the car for the school run could save pound;300 a year
* In Denmark, 60 per cent of children cycle to school. In the UK, it’s less than 1 per cent
* Researchers are investigating the effects of walking to school on brain power
