The traditional approach to ICT requires that schools have a physical server located on the school’s premises. The server (or servers) is typically located in a secure area, with associated networking infrastructure (switches, firewalls etc), and a battery backup power supply (usually known as a UPS).
The server provides user account and security management, file sharing, and other network related management features; with access to these servers being over your local network. For many schools, this remains a proven, cost-effective, and functional solution.