The "School:" namespace is a special feature of Wikiversity. The first Wikiversity pages that made use of the "School:" prefix were the "major Wikiversity schools" corresponding to the list of schools that was developed by the Wikiversity community at Wikibooks.
Historically, Wikiversity schools were arranged into divisions and departments. However, they were little used and were discontinued in 2016. Portals are now used to organize content for similar learning projects.
Schools are dynamically listed at Wikiversity:Browse so be careful about what you include directly in this category.
See also: School.