"Children are a kind of indicator species. If we can build a successful city for children, we will have a successful city for all people."
The last few decades have seen a fundamental shift in how our children get to school, particularly primary school.
When I was a child in the early 70's, 8 out of ten 7 to 9 year olds walked and cycled to school on their own. Now 8 out of ten are accompanied by an adult, all too often in the back of a car. From free range to battery powered within a couple of generations.
Is it any surprise then, as a recently published report from the Commission on Physical Activity says, "in all human history, we have never been so inactive. ... we have simply stopped moving."
That's why we're launching our campaign so children can actually run, walk, scoot or bike the school run again. To make this a reality we need safer streets.
To support our call, write to your MP and let them know you want children to be out and about and active, and to grow up in a world where freedom and independence at the heart of childhood is as attainable for them as it was for us.
Why does this matter?
This isn't just about nostalgia for the loss of something I used to enjoy that my own children don't, like Enid Blyton or Blue Peter.
Only a very small percentage of our children are achieving the recommended daily allowance of physical activity of at least an hour a day. And each year their ability to be physically active by being out and about under their own steam in their everyday lives is eroded as they are put in the back seat and driven, or encouraged indoors to play.
As a result children (and the rest of us) are now sitting far more, even when we're moving. As the Move1 community reminds us, sitting is the new enemy - as bad as smoking on the effect it has on our long-term health and well-being.
The consequence could be years off the lives of our children - years they'd rather put to good use.
The irony is overwhelming
And then there's the environmental impact of clogging up our roads with children being driven hither and thither - to school, to see friends, to parks, to scouts, to soft-play.
The number of hours spent by us parents ferrying children around to places they used to be able to get to on their own, or, ironically, to ensure they get the activity they used to get from front doors, is really mounting up.
One in four cars on our roads at peak time on a school day is taking children to school. Enabling children to walk, scoot and cycle to school would decongest our streets, reduce the traffic jams around our schools, and remove a key justification for building new roads.
And the more we drive, the more we are contributing to making roads dangerous and unpleasant for other road users - like children cycling to school.
Yet the road building mania continues
We are in the grip of a new road building mania, with £billions proposed for new road schemes justified by the need for people to get about more freely.
Actually the solution is to reduce the need for people to drive the over half of all car journeys of less than 5 miles - the school journey being one of them.
This is not the choice of children - nearly half of children want to cycle to school but only 2% atually do so, and children overwhelmingly do not want to be driven. But parents and children are concerned about traffic danger.
The dangers are real
And you can understand why. In 2012 33 children were killed and over 1,800 seriously injured walking or cycling on our roads. To put that in context that's the equivalent of a primary school class of children killed, and over 7 primary schools of children seriously injured every year.
The response to road danger over the years has been a number of road safety campaigns. I vividly remember the Green Cross Man from my youth, and wonder about the correlation between scaring parents, and the decline in children walking and cycling.
No wonder parents and children retreat into cars or indoors.
Of course that's an out of the frying pan into the fire solution in terms of children's levels of physical activity, and the health and well-being that comes with them being out and about and active. That's why our campaign focuses on making our streets safer for children, but of course there are wider benefits.
To quote Enrique Peñalosa, former Mayor of Bogota and a public space visionary, "Children are a kind of indicator species. If we can build a successful city for children, we will have a successful city for all people."
A bit of a paradigm shift, but one that can start by ensuring children have the right to walk, scoot or bike the school run. Let's make it happen!
Melissa Henry is communications director at Sustrans, the charity enabling people to walk cycle and use public transport for more of the journeys we make every day.
Safe to school website: www.sustrans.org.uk/safetoschool.