I was at my local hobby store the day after Christmas and witnessed a father returning an electric train set. Here's what he told the shop owner, "Within an hour my boy lost interest. Half the couplers broke, and he couldn't make a train." As their discussion continued, I learned that the child is 9 years old, and not reckless with his belongings. My guess is that this was the beginning and end of that kid's interest in model trains.
Track used to be the source of most train-set trouble. To a great degree manufacturers have eliminated the problems associated with track, so I would have figured that train sets are a good way to get kids into our hobby. The new thing appears to be couplers. I hope a few manufacturers are reading this because I think this is something they could help with.
I hated horn-hook couplers. They were ugly and hard to uncouple, but they were durrible. Knuckle couplers look better, but the plastic ones are not exactly kid proof. The metal knuckle couplers are more durrable, but they're shot if that little spring disappears. What we need is a kid's train coupler. Make it durrable and easy to couple/uncouple. Appearance is not as important as these factors. I wonder about borrowing from the Brio and Thomas the Tank Engine producers and make a magnetic coupler in which the magnetic force is what keeps them coupled. Put the knuckle couplers in the box, so a kid can convert later.
By the way, my own interest in model trains started when I was 12. I picked up an issue of Model Railroader Magazine at the school library and I was hooked. I saved my allowance and bought a train set, and things progressed from there. I think a good way to get kids into any hobby is to give them access to information about it, then let them develop their own interest. With trains, invite them to go with you to a train show. If they come along, don't forget that they are your guest. Try to be interested at their level, and don't get wrapped up in conversations with your train pals - the kid will feel left out. If they ask questions that seem too elementary, answer respectfully. Of course, leave when they have had enough (you can always come back later to talk to your pals or to spend more time.
Be sure that they have some source of money to finance their hobby. An allowance works great. Teach them to save to buy the more pricy components.
One last thing, if they start becoming interested allow them to learn on their own. Nothing cools a kid off more than dad telling them how to do their hobby. If they ask a question, answer them, then get out of the way and never work on their project! Allow them to watch and help you on your layout and models, but theirs should be their own work. They should have their own work space and tools, and preferably their own layout, all financed primarily with their own money.
Here's to a generation of train modelers,
Phil