...I don't find this manga very impressive at all. Most of the comments before mine have obviously been written by people who have read too much yaoi; in which case their positive reaction to this virtually sexless story is quite understandable.
Thankfully, I am not such a person. Having never read or liked yaoi myself, I feel I can make a much more unbiased assessment of Doukyuusei.
Cliches abound - we have a gay teacher (read: pseudo-rival), an all-boys school (oh why, oh why can't they be in a co-ed school for once 😕 ) and a dash of "Oh, but he's straight so it's obvious that he's just playing around with me until he gets a girlfriend" and "If I go away for college, will our relationship end?" angst to keep things interesting.
I find it difficult to understand how people can think of this as being 'deep' or 'realistic'. There is no such thing as a realistic BL with instantly reciprocated love and an obvious happy ending!
If you enjoy realism, then read The Love Letter, Pokerface and maybe even Boku wa Sakana - all of which are lovely little one-shots that show what really happens to boys who fall in love with their friends.
On the other hand, if you like unrealistic happily-ever-after school-life BL with likable characters, try Honeydew Syndrome or Komatta.
Despite all my criticism, Doukyuusei is by no means a terrible read. It is definitely good enough for a bit of mindless entertainment when you are suddenly struck by the desire to immerse yourself in the vapidly romantic world of shounen-ai. And of course, I'd never miss out on a chance to praise the art; it is lovely, unique and stylized, with not a hint of androgyny in any of the males.
I really hope that Nakamura Asumiko will have the sense to free herself from the constraints of the yaoi / shounen-ai genre and successfully develop the literary potential that make her non-BL oneshots so brilliant. If I'm not mistaken, Utsubora seems to be a step in the right direction.