Dan Dunne (Ryan Gosling) is a New York City high school teacher who today is instructing his class on the subject of history, which he informs them is about the tension between opposites: left and right, big and small, good and evil. The kids are interested on the whole, but while Dan is a good teacher with a great rapport with his students, his desire to instil them with his own lofty ideals about equality and social justice are somewhat compromised by a lifestyle they know nothing about. They have no idea that he spends just about every night getting drunk and worse, getting high, and when an old girlfriend, Rachel (Tina Holmes) shows up, things only get worse...
Half Nelson was based on an award-winning short from the same people, and went on to considerable success in its expanded form, particularly for a small indie that didn't really have any big name stars in it. The most famous actor here was Ryan Gosling, making his name as a talent to watch with some keenly chosen low budget movies and appearances in bigger budget efforts that might not have set the box office alight, but made an impression due to his work. He was given an Oscar nomination for this performance, which only raised his profile further, making it curious he spent the next few years not doing much screen acting at all.
Still, his fans had this to enjoy, as he carried a difficult role with, well, not style exactly as his character spends half the movie stumbling around stoned, but with believability. The idea of a crack-smoking teacher sounds like the indie equivalent of high concept, offering the actor in question to do some druggy acting which in spite of how prevalent it is in films like this, is never very stimulating to watch. Luckily, director Ryan Fleck and his co-writer Anna Boden did not have Dan out of his head the whole time, as he has moments of lucidity such as when he is teaching his class and the world he has so much trouble dealing with makes more sense to him when divided into right and wrong so clearly.
Dan is supposed to be lecturing on the civil rights movement, but after a while you get the impression that perhaps he is not quite the great teacher we had anticipated from those opening scenes. The principal takes him aside and warns him in not so many words that he had better stop rambling and get to the curriculum that he is meant to be sticking to, and we twig that his deterioration is taking part of his professional life as much as it is his personal. The fact that Rachel has showed up to see if he is all right, but for mysterious reasons makes him note that she is now about to be married, doesn't help and Dan ends up one evening after coaching basketball slumped in the school toilets doing crack.
Which brings us to the other character who takes up half the movie, and she is Drey (Shareeka Epps), a thirteen-year-old student of Dan's who finds him wasted in the bathroom. A curious relationship develops between them, with each believing that they should be saving the other, Dan from his addiction and Drey from being groomed by local drug dealer Frank (Anthony Mackie) into selling for him. Drey knows that Frank is up to no good, but he treats her so well that he becomes the substitute for her brother who is in prison, and a battle of wills over her erupts with neither side exactly the most responsible figure that the girl could be guided by. Dan, it is implied, lives in a world of noble ideals that he fails to live up to, while Frank is an intelligent member of the real world, the street if you like, but doing nothing to lift those he meets out of the gutter. If it were not for the performances Half Nelson would have been too studied and contrived to satisfy, and there are too many stretches where you feel a simplistic lecture is on the way, but the actors do it justice. Music by Broken Social Scene.