When you apply for a building permit, school fees (sometimes called school impact fees or school facility fees) are typically charged to developers and property owners to help fund local school infrastructure. These fees are designed to offset the potential increase in school-aged children that might result from new construction or property development.
Even if you don't have children, the reasoning behind these fees is that:
New construction or property improvements can increase local housing capacity
New homes can be lease or sold to families with children
These fees help local school districts prepare for potential increased enrollment as projects increase housing unit density in a given school district.