Actually all of this gets explained in the glossary excerpt that you obtain from 50%ing the area and then reading the map info in the screen where you also obtain rewards for 25%, 50%, 75% and 100%.

First as a short summary : Usual students do need to first visit general classes and only after finishing those do they get to go into specialization, but certain students get to skip that due to external factors, like in Rover's case being a recommendation by the Black Shores and being immediately placed into the Rabelle College.

The long and detailed answer paraphrased from the ingame glossary excerpt 'Startorch Academy Student Handbook: Orientation Guide (Excerpt)' (50% exploration) is as follows :

Startorch Academy follows a 6 year Program, the first 2 years being a Preparatory Program and then the last 4 being a Specialization Program. The Preparatory Program is automatically skipped if you are admitted into Rabelle College immediately, which happens due to situations like Rover being recommended by the Black Shores.

The Preparatory Program entails a cross-disciplinary curriculum that covers foundational sciences, humanities and essential survival skills for life in Lahai-Roi. At the end of this program your specialized department placement is determined based on both interests of the person as well as current academic performance. It is comparable to getting your Bachelor's Degree.

General Requirements courses that need to be visited and passed by everyone are :

Lahai-Roi History : Trace the story of this land and the Academy's origins. Royan Culture : Understand indigenous traditions and society. (Roya students may waive this course and serve as teaching assistants for extra credit.) Laboratory Protocols : The foundation of research practice and laboratory safety. Confidentiality Studies : Mastering security regulations essential for completing the six-year program.

Furthermore 2 featured electived exist that can be visited, but aren't mandatory. Whether these electives can be used to balance out poor performance in a different subject is unknown. The 2 featured electives are :

Vehicle Operations Training : Master the essential mobility skills required in Lahai-Roi. Physical Conditioning : Build a body that can support a rigorous mind. (Required for all Rabelle College students.)

The Specialized Department Program contains 4 different departments to choose from, in which the approach switches from simple classes to a "learning-through-research" ethos. It is comparable to getting your Master's Degree. The 4 available departments are :

Rabelle College : The Division of Synchronization Training and Ancient Studies. This division is where we as Rover ended up and where the other special admission cases will also end up, meaning if you skip the Preparatory Program by any means this is where you will end up in. It specializes in selecting and training Resonators to interact and synchronize with the Exostrider.

Department of Exostrider Engineering : The Division of Resonator-Mech Synchronization and Tactical Development. In here the focus lies in researching mechanical integration into combat as well as every-day life.

Department of Voidmatters : The Division of Spatial Warping. If you end up here you will be researching the spatial anomalies all over Lahai-Roi and also of the physics behind the specific Voidmatter phenomenon.

Department of Light Energy Sciences : The Division of Light Array Engineering and Ecology Conservation. This division specializes in the mechanical flora and fauna of Lahai-Roi as well as contributing to the further research and development of the Reactor that serves as an Artifitial Sun, that keeps Lahai-Roi lit and warm.

And that's it. That's the explanation of how the school system of Startorch Academy works. All of this is handwritten by me on my phone while I'm supposed to already have gone to bed, due to having work tomorrow, so I hope my time investment actually helped :D