The proportion of Scottish pupils walking to school is at its lowest for at least eight years, a survey by cycling and walking charity Sustrans showed today.
The annual Hands Up Scotland poll found 42.9 per cent walked last year compared to 48.3 per cent in the first survey in 2008.
It said there had been a "steady decline" from 45.8 per cent in 2010 - the first year all council areas took part.
The total fell from 47 per cent in 2009, when all but three councils were involved.
The proportion travelling by bus also declined, to its lowest level, from 18.2 per cent in 2010 to 16.7 per cent.
However, cycling has increased from 2.8 per cent to 3.5 per cent.
Scooting or skating also went up, from 0.7 per cent to 2.8 per cent.
But such "active travel" fell overall for the second year, by 0.5 percentage points to 49.2 per cent.
The numbers being driven to school by car or taxi increased for the third year to 24.2 per cent, but it is largely unchanged on 2008.
However, there has been an increase in pupils being driven part of the way and walking the rest - or "park and stride" - to 9.3 per cent from 7.4 per cent in 2010.
More than 450,000 children - nearly two in three state school pupils - took part in the survey last September, which covered three in four state schools.
Scottish Labour said it would counter the drop in walking by getting pupils to run a mile a day while at school.
A spokesman said: "It's essential we encourage children and young people to do as much exercise as possible.
"Our manifesto commits Scottish Labour to the introduction of the 'Daily Mile' in schools across Scotland.
"We have seen the success of the “Daily Mile”, as started at St Ninian’s Primary School in Stirling, in improving health and educational outcomes, and we will support its introduction across Scotland as a normal part of the school day."
Scottish Conservatives transport spokesman Liam Kerr said: "These figures are clearly disappointing, and show we need to think more strategically about making it safe for children to walk, scoot and cycle to school.
"The Daily Mile is a great initiative and should be encouraged in every school, but that should not be viewed as a replacement for active travel.
"We need to explore ways of getting parents out of their cars and making it easier for children to choose the healthier option.
"This will require action at both a local and central government level."
Stuart Hay, director of Living Streets Scotland, which promotes walking, said: “The number of children walking to school is holding up despite multiple challenges, including a move to larger school catchments and concerns about traffic congestion.
“The situation won’t improve until all Scottish local authorities actively promote walking to school to overcome parents’ fears about safety.
"This needs to be supported by action to tackle school gate congestion, such as street closures.
"Finally, it is important to avoid ever bigger schools with catchments that make walking challenging.”
Sustrans Scotland national director John Lauder said: “The survey is crucial in helping local authorities and partners to build a more accurate picture of how Scotland’s children are choosing to travel to and from school, and helps to pinpoint areas where more work can be done.
“Research has shown that increased physical activity can help us lead healthier – and happier – lives.
“By encouraging young people to travel actively for their journey to school, we can ensure Scotland’s children develop healthier travel habits that will be continued later in life.”
A spokeswoman for Transport Scotland, which funded the survey. said: “The Scottish Government continues to work with local authorities and wider partners to encourage walking and cycling for travelling to school.
"We are pleased that cycling rates have increased since 2010, and that active travel continues to be the most common way for pupils to travel to school.
“We will continue to support all active travel to school, and in particular, this financial year, we will fund Living Streets Scotland to deliver their ‘WOW’ programme encouraging walking to school to an increased number of schools across Scotland.
“Local authorities have a number of tools which they can use to encourage walking and cycling to school, such as 20mph and vehicle exclusion zones around schools.
"We continue to fund local authorities directly with a cycling, walking and safer streets grant, which this year is just over £7 million.
“We made a commitment in our Programme for Government to at least maintain our record investment in active travel, of £39.2 million annually, to 2021."