I have taught in a few different high schools in a few different states. Many of my students were football players and serious, but they were still kids and liked to laugh. I think the portrayal of high-schoolers as men and dutiful warriors in FRIDAY NIGHT LIGHTS was cinematically compelling and starkly beautiful, but not truly authentic, which made it work to watch. As a result, I stayed away from the television series. But this fall I came back around and watched the series--without commercials, which is the only way I can watch television these days--and loved it. It came to life for me because of the larger role of the coach's wife, but also for the humor, especially generated from the teenage characters and their dialogue. Since I started watching the series, I have learned that many of the actors, including those portraying the teenagers, were able to ad-lib lines. In many respects, I think it made their dialogue more authentic and funnier. My experience with kids has shown me that they are curious and confused and bursting with things to say if you give them a chance. And what they say is generally hilarious!
So, thank you, Peter Berg (creator of FNL) for giving these kids/characters more dimension. Their humorous dialogue (maybe not five seasons worth, but still) made the series more authentic and ultimately more watchable than the film.
If you have not seen the series, I recommend watching the pilot and the first episode of season four. Not surprisingly, they were the episodes that Berg directed.