They Showed Up at High School?
I have had High School Years since it was released. This is the very first time Teens from another household actually showed up on campus. (And I'm not talking about NPCs.) I have only two households...
Forum Discussion
A lot of the game's "filters" that determine which sims are "eligible" to fill positions exclude households marked as "played". Sims in "My Households" are excepted from showing up as vendors and such.
The HSY Student filter specifies that it wants "Unimportant Sims" only, which often excludes played households. The point of that is to prevent your storylines you're telling from potentially being damaged by having Sims show up places they shouldn't be. Whether or not that makes sense for high school I'm not sure.
It's possible played household Sims only get called for High School if there aren't enough "unimportant sims" to fill the rest of the classes. The game may be saying "use unimportant sims first, and then played teens, and then generate new teens if not enough sims are available".
