Well, in my opinion high schools are of borderline notability.  Usually high schools have tens of thousands of graduates, each one spending hours and hours there for a four year period with countless memories during a time of transition in their lives.  Some have more students than say Bryn Mawr College.  Also, to try to delete every article on a high school is an unspeakably futile act.  It just can't happen, and even if they were deleted they'd just pop right back up like weeds.