The movie is mediocre. I saw the director in an interview saying that the movie treated the problem of the suicide in high-income guys in Mexico. Honestly, the movie is basically a love story of Diego Luna (the main character) with three girls (by the way, having a lot of sex) and barely analyzes the situation of the suicide. Far from any real situation. A side note: the girl called Tania is gorgeous (i.e. una preciosa morenita).
Besides the drama, this movie portrays the complicated situation that teenagers face in Mexican secondary schools. That is not unreal. P.S. Few graduate students in the US have actually attended to public secondary schools.
The short story starring Gael Garcia is by far the best. That short film is a real portray of a love story in "the real" Mexico City. That is not love of "nice" people, but love of people who live and grow up in the street.