I don't see about setbacks, but:
6.08.150 - Animal confines—Shelters.
A. It is unlawful for any person to keep or maintain any animal in any yard, structure or area that is not clean, dry and sanitary, free from debris and offensive odors that annoy any neighbor, and devoid of rodents and...
6.20.010 - Running at large prohibited.
It is unlawful for any person to suffer or permit any chickens or other domestic fowls owned by him or in his charge or under his control to run at large within the city. The term "at large" shall be defined to include those times during which any chicken...
Naw, schools are probably in the city regardless of who owns them, they're not like embassies.
Nobody will attempt to enforce that law that way, because that's not what it's about, but it is what it says.
Hmm. To me this code means you can keep chickens in your yard:
It is unlawful for any person to own, harbor or keep within the city any wild or domestic animal, fowl, bird and reptile, except as hereinafter provided:
D. All household pets other than dogs and cats, shall be kept and maintained...