@TrinityNoel25 Are they not going while you play them or while they are NPCs ?
(just making sure, it sounds like that's the issue).
You'll currently need a mod to pick which NPC Sims are at high school.
@TrinityNoel25 Hi! I thought I might mention that I had some success getting my created teens to spawn by going to Manage Households and deleting some of the premade teens. If you don't want to delete them, you could try using the cas.fulleditmode cheat to age them up. Depending on how many unplayed teens are available, the game may still generate NPC teens to fill the classrooms.
That being said, I personally use a couple of mods that I think work well in tandem to get some of my created teens to spawn. We're not allowed to link to mods here so you'll need to do some googling. :-)
- High School Years Tweaks mod by Simvasion. It basically tweaks the tuning to favor your teens' high-level friends to spawn at the school.
- More Students at High School mod by ksuihuh. This mod has three versions that allow for 18, 24 and 40 students. I like the 18 students version because it fits the in-game classroom size perfectly; 9 desks per classroom, 9 students per class.
I did some googling myself and there is another mod that looks interesting called High School More Class Mates by Aramiteus which is on the nexusmods website. This one appears to be a bit more complex with multiple features that includes choosing who your sims' classmates will be. Another one that is available on CurseForge is called Choose Your High School Classmates by konanhurry. Maybe you could do some more searching and find others that would suit your needs.
EDIT: After reading a bit more about the Classmates mod by konanhurry, I noticed they shared some insight about some game requirements for the teens that spawn. I'm adding their note in a spoiler here.
If you do decide to try mods, I always suggest testing them before committing to make sure they don't break your game or make changes that you don't like. Please use the "save as" feature in game options to create a safe place to test mods and to keep your current game in tact, just in case. If there are no issues, you can just continue using the test save but if there are problems, then at least you can go back to your original save. Hope this helps!
