The big thing is usually old building stock. Urban school districts in the US are disproportionately in old buildings that have high maintenance costs, low eff

The big thing is usually old building stock. Urban school districts in the US are disproportionately in old buildings that have high maintenance costs, low efficiency for utilities, and have all sorts of problems that need remediation, like lead or asbestos. There is generally no capex money to replace these buildings, and even if there was, finding a suitable property in an urban area is pretty difficult, since schools are big.