I believe there are so many factors which go into fostering a love of the Catholic faith in young people. Obviously, the primary factor should be parents who also have a real love of the Catholic faith who instill this love into their children through attendance of Mass and other Church events, through family prayer and devotions, and most importantly, through a good education which integrates the faith into all of the other areas of study.
However, it’s obvious that many young people today do not have this most effective way of having the faith instilled in them. I would say that since parents often still have the most influence on their children, I think the solution to modern-day indifferentism towards the faith among parents must necessarily involve them, to the extent they are willing to be involved. This may mean including them from the beginning if they are willing. If they are not willing, but still willing to let their children find their own way, then one of the first steps is to have a very solid youth group, with a solid young adult overseer which instills leadership skills into a few of the able teens. Obviously peers are a HUGE factor in teens’ lives, so I believe it is essential as well to have good peers who are willing to lead.
I guess what I’m trying to say is that fostering a strong, faith-filled community/family-type group is the way (or at least, a way) to go. Involve the parents as much as possible/as much as they are willing as well - be active in having events which parents are more than welcome and encouraged to attend and be a part of the group and their kids’ faith lives. If they won’t come, then fine - it is the kid who will suffer, but if the peer group is there for them, that will have a huge effect on their life and could equip them with the faith life they need as they go through high school and enter college and adult life. They need the good examples from both adults (parents and otherwise) and their peers, to show them all of the wonderful richness of our Catholic faith, to give them the tools they need to grow in their relationship with the Lord. Expose them as much as possible to Beauty, Truth, and Goodness.
The young people are THE future of not only our society, but more importantly, the Catholic Church. We need parents to be extra-involved with their children’s faith lives, and we need on-fire young adults who are willing to not so much take over the parents’ roles, though in some cases they will inevitably do so, but more so to give back the role of instilling faith and good examples to the parents, whose duty it is to do so in the first place.
P.S. - I don’t mean this last paragraph to mean that teens and young adults are the only ones who can offer anything to the Church. Just that since young people are so impressionable and malleable, they absolutely need the examples which they deserve but are not getting these days.