This isn't one of those cliche shounen manga where all significant details are explained in the first couple of volumes, with the rest of the series being expended on training sessions and meaningless filler arcs. If you're expecting something typical to this demographic, Torikago Gakkyuu is not for you.
So far the story is quite interesting, and since the protagonist himself is struggling to figure out the reason for his sudden imprisonment in this unusual 'school', it's obvious that the readers would be confused as well. The personalities of his teachers and classmates are bizarre and deliciously twisted; the story provides an eclectic mixture of social commentary and supernatural mystery which I personally find very intriguing -- quite unlike anything I've seen before.
One issue I have, though, is how readily Mikage accepts his inexplicable confinement and the odd behaviour of those around him. But recent revelations promise a satisfactory explanation for this less-than-sane reaction. Hopefully, the developments in later volumes will not disappoint.
And...pseudo-yaoi interactions? What!? Between who and who, exactly? There is no such thing; if any, there are some pseudo-romantic interactions between the supporting characters...but their personalities are such that this manga is unlikely to ever become 'romantic' in the conventional sense.
The art is elaborate and atypical, with a darkness that caters appropriately to the moody atmosphere permeating the story.
A good choice if you're tired of standard shounen fare and looking for something darker and more well thought out.
(The previous summary was, admittedly, not detailed enough -- I've altered the description)