PPIR has the Bondurant school. I was at PPIR this past weekend racing with NASA and saw the Bondurant cars, don't know how their school is.
FAASST is in Pueblo. I've attended a few Military Charity lapping days with FASSTT, but not a school. I like that they walk the track with newbies to show them things to keep their eyes open for before setting rubber to pavement. Judy just took over running the Pueblo track this year, so it'll be interesting to see how she balances the school and track maintenance.