Edit: I thought this was the Off Topic/Everything Else section. Whoops! I'm truly sorry about that.
Which have you seen and which do you prefer and where was it? I've been to schools when I was a kid both in Oregon and Northern Cali and even in the mountains of Northern Cali at least where I was every school the hallways were exposed to the elements though they were covered against the rain or snow but never have I seen a school completely enclosed. The doors to the classrooms all opened to the elements so in the winter when a student or teacher opens them BURRRRRRRRR!
The only indoor areas were the offices and cafeteria/MP room.
Now in Oregon I can't find a single outdoor hallway school they are all the indoor hallways though around here you go in and out of various buildings so I guess you get SOME outdoor exposure not including mods. I assumed in Central Oregon schools would again have the outdoor hallways using the (California model design) due to the dry climate with very little rain/snow but when I have gone over on vacation and drove by I was wrong and shocked to see the same enclosed schools.
BTW: Did your school have mods used as classrooms where you had to go outside to get to them? Mods were fun actually.