In my Isla Paradiso save my kids can enter the school building but the "go to school" action will drop from queue. They aren't getting reset and there's no error message. I can zoom in on the rabbithole shell and see them standing there, now skipping school. Resetting the lot or world allows them to attend the next day, but only for that one day. There are 15 children/teens in my world plus 5 in my active family; maybe that's too many? I installed a second school using a rabbithole rug and have nraas Careers installed as well so the kids should be pretty spread out. It happens with the regular IP school and the theater and iirc the science lab before I installed a second lab.

How do I keep the little gremlins in class?

If you have or can add in NRaas DebugEnabler, try running its Fix Homeworld command. Sometimes homeworld assignments get out of alignment and that prevents sims from going to/staying at work or school. The worst thing it can do is respond that there is no one or nothing to fix.

15-20 school kids is not overload for a world with multiple schools. One of mine had over 80 teens and 20 children with four public schools, some distributed among the Careers mod specialty schools, and some home schooled at one point. Prom night was a mess because of all of the teens in town trying to converge on one lot at the same time, but other then that the gremlins managed to mostly stay in their respective classes. If a school or career rabbithole ever blurps out everyone inside in the middle of the school/work day, I would try to catch the inactives if I notice quickly enough and use MC's Go to School/Work commands on them to get them back inside.

This mod can help a lot with overcrowding at the entrances if you aren't already using it.
http://modthesims.info/d/568897

I'm constantly learning new things about the nraas mods. I'll try the debug enabler, thanks.

I think installing DebugEnabler is a must if you have so many sims mods as I have. Almost all my issues I resolve clicking on "">Nraas>DebugEnabler>Options: "">Sim>Fix ""

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