NPC sims not teleporting to high school

I got High School Years and when I joined my Sim when they went to High School everything worked fine. Then, I got a mod that added more students in the classes, and even the my game worked fine. I eventually removed that though, and got a different mod. That's when other Sims stopped showing up to school. I removed the mod because I thought that the cause for the other Sims not showing up. But the Sims still weren't showing up, I eventually gave up but now I want to fix this problem. Are there any mods that i should remove from my game that would cause this to happen. Let me know, thanks.