@kageoukami Just to be clear, are you placing a standalone school and a standalone stadium, like the ones you see in Sunset Valley? Sometimes the game needs a day or so to reset the available functions on the lots. You could try building what you want, and then using "save as" with a new name for your save, then quitting and reloading the town. If the issue doesn't resolve itself in a sim-day or two, then you know you have a problem. If so, I'd recommend using a lot from a town where you know the rabbitholes work, like SV or Riverview.
Just a note, if you bulldoze the original building before placing the new ones, adult sims who work there will lose their jobs, and children enrolled in school will reset their school performance to zero. This can be avoided if you make sure that there is always at least one building on the map at any given time, even while you're in Edit Town. Again, the townies may be confused for a day or two as to where they ought to go, but things tend to sort themselves out rather quickly.
