Did you get the "On the Clock" bug too?
I had the issue and what worked for me is to save family and their house separately via Edit Town. Then evict family, bulldoze home, replace home and replace family.
If you don't want to try that you could try:
1. Reset Town/Evict or Move Household and move 'em back in.
2. Quit and join profession again.
3. Try going back a save before the experiment.
You might try experimenting in a test-save instead of your main game. At least for the Daycare career. Since it seems sensitive to any kind of change. Though this seems to be the case with any Sims 3 career.