Outside our house and The Grange School

Our driveway is being obstructed on a daily basis by staff and pupils at the school and is of grave concern due to the risk it poses to children and other drivers. In my professional role, I am regularly out in my vehicle and therefore need to be able to leave my property safely. Currently the driveway is frequently obstructed during school drop offs and picks up (8.15-4.00) but this has got progressively worse with people now parking on our drive and over the driveway for the entire school day (see attached two pictures of different white cars). When trying to get onto my driveway at school closing times, I have often had to wait obstructing the road until someone has removed themselves from my driveway. The space between our in and out driveway as far as we can see is unnecessary as we have ample space on our drive and just encourages people to park across it. We have tried leaving polite notes and contacting the school. However, as it is outside of the school gate they have said that there is not much that the school can do. Furthermore by having a space here, rather than a double yellow line it puts both school children and others drivers at risk as we cannot see to get out of our driveway and are at risk of being hit by others cars or hitting another car or child. In my professional role I have a duty of care to children and I cannot understand why Bucks cc would not have a double yellow instead of a parking space given the near misses we have seen. Should there be an accident of this nature I believe that Bucks cc would be may be found to be culpable, given that we are directly across from a school and the schools main exit and yet there is an invite to park directly opposite.