I think that Hinton's work is meaningful in terms of the genre of young adult fiction. There is a certain level of experience and narrative that can be understood by many students as the book identifies critical issues that are an integral part of adolescence. The idea of being excluded from a social order, displaced from family, and seeking to find belonging with friends and peers are essential to the adolescent maturation. At the same time, having to make critical choices about identity and living with the consequences of those choices are also extremely vital elements to the maturation process, making the book one that can find relevancy today. Of course, there is a dated aspect to it, in that much of the modern setting cannot be found in the novel. However, if we take the characterizations and development of their identities, there is much in the way of relevance to modern readers and students.
If I hadn't taught this book, I would have said that it was irrelevant today. However, I have never met a student who did not like this book. As a result of this, I would have to say that The Outsiders, by S.E. Hinton, is still very relevant today. Sure, there are some elements of the book that are outdated, such as the way the two groups dress, and some of the vocabulary that is used, but a novel like The Outsiders has universal themes with which everyone can identify. What student doesn't understand important messages such as loyalty and friendship? The whole "stay gold, Ponyboy" thing is a little cheesy, though!
Some people might find Susan Hinton's teen novel, The Outsiders, a bit outdated in the 21st century, but I don't find it that way at all. Many of the characters' problems in the novel--social acceptance, family issues, parental neglect, school life, teen angst--are still relevant today. Perhaps an even greater issue is the resurfacing of gang activity during the past two decades. While gangs in the United States virtually disappeared during the 1970s and 1980s, they have obviously returned in great numbers in recent years. I think many readers would still be able to relate to The Outsiders today. Certainly, the movie version, starring many young actors who hit it big shortly thereafter (Patrick Swayze, Tom Cruise, Rob Lowe, Matt Dillon, Diane Lane, Emilio Estevez) is a great supplement to the novel.
There is not really much about the book that is irrelevant -- not much that doesn't apply today.
There are a few little things -- hair length isn't such a big deal today, there are no drive in movies, I have no idea what a Madras shirt is.
But those are minor details. The issues that the book is about are timeless. Teens will always feel like society does not like them. Teens will always feel like they are not sure who they are. They will always want to feel like they belong to a family. Most boys will feel pulled between anger and violence on the one hand and being "gold" on the other.
I think The Outsiders is a brilliant book but I don't think it is relevant to today. It has too many people with long hair and I hate long hair. The cars are bad because I only like Ferraris and I hope that they invent them in the book quickly otherwise I could not stand it. As I said earlier Stay gold Ponyboy is a brilliant catchphrase that many football teams would use in their chant today and I hope they eat it with cheese. Please don't eat icecream with noodles on top because last time I did that it spilt everywhere and tasted like golden syrup.
Thanks I hope that answered your question.