One recent morning I witnessed a rare sight; two children, almost certainly brother and sister, were riding their bikes to school. They wobbled along the sidewalk of a busy road. The boy pedaled ahead on his BMX while the girl’s bike was too big for her, its chain rusted to the point where, rather than shift gears, she walked the slightest rise. Commuters alone in their cars sped by on the way to work, their kids’ schools, gym or supermarket. This being outer Sydney, the street made not the slightest accommodation for the two kids and their healthy, intrepid mode of transportation.