How do I research more rooms in Pocket Academy?

Question

I have a number of rooms which I know are in the game because they show up in the spot guide. However, they don't show up in the list of rooms I can currently build, and are not available as options in the research menu. I haven't had any new options in the research menu appearing from year 5 to year 8, which I am currently on, other than those which I get from students who just graduated, like the bronze statue and similar. What do I do to unlock more research options?

Answer 1

This wiki page shows what I was missing. Certain structures require you to have a certain quantity of specific structures already built, along with size requirements. For example, the baseball field requires 3 basketball fields and 3 tennis courts to be built in your school.