I always loved S.E. Hinton's novels as a kid: The Outsiders, Rumble Fish (which in my opinion, is the greatest film adaptation in the series despite everyone's fascination with The Outsiders), Tex, and That Was Then This is Now.
'That Was Then, This is Now' was the last film adaptation (although the TV series for 'The Outsiders' follows five years later after the release of this movie). I would've attribute the mediocrity of the movie, or at least the inability to really put forth all that the novel did, was because it was not directed by Francis Ford Coppola (who directs 'The Outsiders,' and does a fabulous job with 'Rumble Fish'), except 'Tex,' which was a pretty good movie, was likewise not directed by Coppola.
I think it is in part the chemistry among the characters. The whole mood looks like something out of a music video, with Craig Scheffer coming off more like a guy who broke off a long relationship with a girlfriend rather than dealing with a rambunctious brother (in addition to other things). Plus, as another viewer already mentioned, they shifted the focus on characters so that superstar Emilio Esteves becomes the center of attention. Most of S.E. Hinton's novel always portrayed a struggle from the brother who is looking out at things that, by his perception, have become (or always were) seriously out of control. (See 'Tex' and 'Rumble Fish'). And yes, they unfortunately acquiesced to the Hollywood happy ending, and in the sappiest way, despite all of the problems that the characters endure.
Unlike previous adaptations of Hinton's novels, even those not directed by Coppola, they really fail to portray the struggles that the characters realize in the book. And, lack of developing the story on this point really makes you only half appreciate the characters and their conflicts (and in this case, not even their resolution).
