We don't see too many kids riding to school here.
Several of the elementary and middle schools are perched up on the hillsides, with the access roads far to steep for children to ride up. The high schools' catchment areas are too large for many of them to make cycling practical, even if they weren't either located on roads too heavily-automobile-trafficed to make cycling safe, or (in the case of at least one) up on top of a mountain.
A couple of the schools down 'in the flats' have bike racks, but they aren't that much used. There isn't a districtwide policy against it, but it is certainly not encouraged.
When I lived in Charlotte, NC, I taught in the public schools, and there was a district policy forbidding cycling to school.