The main setting of Tanaka-kun Is Always Listless appears to me to be extraordinarily fancy, at least by my American experience of going to high school in Wisconsin.
Do those poles along the building support a net, maybe to protect windows from stray balls? The surrounding area is beautiful, with a rural forested feel and located near a river.
It appears as if one end is open, and there are other shots of small patios upstairs. Apparently they do not air condition the middle area -- it is sort of a breezeway, albeit with one end partially closed off. I am impressed by the sunroof, the middle downstairs area which appears to be some sort of courtyard or atrium, and the upstairs walkway which reminds me more of an indoor shopping mall than a high school. I don't remember other anime where the high school itself was so interesting.
Wow, a Google search for Japanese high school architecture starts off with 5 more affluent-looking schools. Maybe the word architecture tuned the search for high end samples. It gets even more impressive if you click over to Images. This ain't Wisconsin.