I can’t remember the title but I know it was about a school that was supposed to be thirty rooms horizontally but the contractor made a mistake so they ended up with one straight up. Does this twig anyone’s thoughts?
I think I recall seeing a title that might fit, something with a pun on ‘wayside’ ‘sideways’, like The Wayside Sideways School. I didn’t read it, but I do recall the front cover had a 30-story building on it.
There was two books - “Wayside School is Falling Down” and “Sideways Stories from Wayside School”. Both were by Louis Sachar.
Being under 21 comes in handy for once!
“Sideways Stories” was the first. There was another one as well, “Wayside School Gets A Little Stranger,” I believe. Sachar may have written more, though.
You can always check on amazon.com. Have fun, but remember, there is no 19th floor. 
I loved those books! “Wayside School is Falling Down” is HILARIOUS! (Or it was when I was in 3rd grade…)