I am surprised at just how little I've found about the Schola Progenium Organisation apart from the odd bits in the FF books and *** bits about famous progenia on the net.
There is a description in the Codices (2E SoB and 2E/5E IG), as well as some more bits in the Inquisitor RPG. However, depending on how your party looks like, this material may not be of much use as GW studio fluff generally describes the Schola in a far more limiting and oppressive fashion than certain novels. The environment does have potential, but depending on what your players are looking for in a game it'd probably take some "incident" to actually make it playable by removing the class from the standard daily schedule and/or allowing progena of different sexes to interact with each other.
For inspiration, perhaps the movie "Before the Fall" (see trailer here) may be of use. It's about one of the infamous Nazi-German Napola (short for Nationalpolitische Erziehungsanstalt = Institute for National-Political Education) academies and basically tells the story of one student's life there. In my opinion, it's fairly close to a Schola Progenium, although the Schola is probably even worse when you think about it.
current 40k RPG character: Aura Vashaan
, Astromancer Witch-Priestess
previous characters: Captain Elias (Celestial Lions Chapter -- debriefed), Comrade-Trooper Dasha Malenko
(1207th Valhallan Ice Warriors -- KIA), Sister Elana
(Order of the Sacred Rose -- assassinated), Leftenant Darion Baylesworth (Rogue Trader Artemisia -- retired), Taleera "Raven" Nephran (Hive Ganger & Inquisitorial Assassin -- mindwiped)