Mostly Windows 10 - supports even 32-bit CoreDuo, all edu software works, staff knows it. In EU you can buy second-hand software licenses legally. Some schools

Mostly Windows 10 - supports even 32-bit CoreDuo, all edu software works, staff knows it. In EU you can buy second-hand software licenses legally. Some schools participate in volume licensing schemes with MS too. But I also install Ubuntu on some specialized "workstations", e.g. pendrive/Internet terminal laptop connected to beefy old laser copier/printer where CUPS PCL works with zero drivers. Other use case: jukebox laptop for music classes :)