Ixiah I actually never paid attention to whether the education gains
from lessons themselves can be negative, and assumed they cannot, which means having teachers teach every subject is more beneficial - "50% of something is better than 100% of nothing", after all. Not to mention that
the teacher gets more proficient at the subject the more they teach it, so if you have everyone teaching every subjec, eventually your teachers are going to be proficient in everything. Unless there is something I am forgetting, for a casual non-grindy playthrough this does not matter much.
Of course, not every subject needs to be added to the curriculum, in the first place, but that is another topic altogether.
I THINK that, if you try to min-max education gains, you PROBABLY would go "only the strong subjects" (at least for the first few months/teachers), but you would have to adjust the curriculum accordingly, i.e., remove subjects not covered by any of the teachers and add the ones that are.
I just go for "I have stamina limits, you do not - TEACH EVERYTHING, lazy bums" every time.
![Roll eyes :rolleyes: :rolleyes:](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)