Have you thought about bringing up the safety concerns with the school's PTA? Our local PTAs would be all over it! And they also provide a place where parents can come together as a voice that can sometimes influence school policy on issues like this. Depends on the school and district of course, but it's something I'd definitely consider.
If you continued to get push-back from the school's principal, I'd also consider networking with parents at other local elementaries, see if they have similar concerns, maybe consider taking the issue to your school board or going together as a group to talk with the district administration.
I can't imagine that you'd have any problem at all finding other parents who share your concerns!
polarbear
