Microsoft programs include K-12 license program based on FTE count, OVS-ES and individual version licenses.
K-12 Site/District Licensing
Microsoft offers unlimited installs on all school owned/leased computers of three campus wide products, Office Pro Plus, Windows Pro Upgrade and Core Client Access License. This program is call the OVS-ES and provides Office 365 for Teacher and Student home use with a campus wide
Version licenses are the more traditional approach to software licenses. These are perpetual, current version titles. These titles include Windows Server, SQL Server, Windows Pro Upgrade and Office.