Preserve school playing grounds

Preserve all school playing grounds from developers. Ban their sale. And reverse the sale of any sold in the last ten years, e.g. St. Paul’s Raheny sports grounds in St. Anne’s Park. How to afford it? What is the cost for children who cannot play to their health, obesity etc. ? There is a lot of money owed to the state to redress boards, that may be a good place to start.