To help you plan the layout of your Springfield, here’s what the Adult Education Annex looks like once it’s in your town (as you can see, I’ve had to leave it un-landscaped for the moment as I’ve run out of money!):

Available as part of the level 27 quest, it costs $182,000 and, like El Chemistri, takes 36 hours to build. You get 20,000 XP on completion (subject to bonus multiplier adjustments).