At least 60% of children in England should be walking or cycling to school within a decade under the government's new active travel plans.
Ministers say millions more five-to-16-year-olds will be able to travel by foot or bike using thousands of safer routes promised under its "record" £4.5bn investment strategy.
At least half of all short trips in towns and cities should also be walked or cycled by 2035 and a "national walking and cycling network" will be available on route mapping apps within five years, under the plans.
Transport Secretary Heidi Alexander said the strategy sought to make active travel "a practical choice for millions more journeys".
The latest government data, from 2023, suggested that 47% of children aged five to 16 usually walk or cycle to school.
Some 5,000 walking, wheeling and cycling routes and 10,000 "safer" crossings will be built by 2030 to meet the new target, the Department for Transport (DfT) said, which will be delivered alongside local authorities and Active Travel England.
There will be £135m spent on programmes training children to walk and cycle safely to school, and to help schools develop travel plans - although it is already commonplace that they encourage pupils to avoid car journeys.
Ministers also want 55% of short trips to be active by 2035 - including what is described as a "stage" of a journey, such as walking or cycling to onward public transport. The current level is 48%, according to the DfT.
The increase would mean 5.3m more people being physically active in towns and cities, ministers say.
The strategy also sets out plans to develop a national active travel network that is "usable at a national scale", including consistent signage and availability online alongside the road network.
Transport Secretary Heidi Alexander said: "Too many people would like to walk, wheel or cycle more often but don't feel they have safe and convenient options to do so."
"This is about creating healthier communities, helping households keep more money in their pockets and building a transport network that works better for everyone."
Health Secretary James Murray said the plan would "help more people build exercise into their everyday lives, improving public health and supporting our ambition to reduce pressure on the NHS".
