One of my dc is disabled and has a blue badge. They are not at school yet, but often come with me or dh to drop/collect siblings.
There is one disabled parking spot at school, however we are rarely able to use it due to a number of ‘repeat offenders’ who use the spot despite not having a blue badge (or at least without displaying one). One person in particular likes to mount the kerb, I think in an attempt to not quite park in the spot, however this makes it impossible for anyone else to actually park in the spot 
AIBU to report to the school? maybe a reminder to not use the space unless displaying a badge would solve the issue? I don’t want to make a fuss, and hate anything like this that reminds us of my dc disability, but it’s getting very frustrating...