The best thing you can teach your children so they continually learn is to ask questions. The more they ask, the more they will develop a natural curiosity. You can't really force a child (or even a person for that matter) to learn, unless you use some sort of punishment for failing to learn, which is detrimental and can cause the subconscious fear of failing to learn, and in essence, hatred of learning.
The best ways I've found to learn is by hands on approach, especially when I was younger. Kids are active learners - they like to do things on their own and figure things out for themselves when they can. Not only are they active, they are interested in things because of the fun factor. A child doesn't chase down a frog because you tell them "Hey, go learn about amphibians," they learn because they want to. When things are fun, learning is easy. I like to give props to Randy Pausch's "head fake" technique: where you make something fun and people don't realize they are learning something.
As for me, the best way I keep learning is books and tutorials (for my tech side). I learn a lot more for tutorials than I do from books, but that's just my hands on learning style.
If I need to solve an immediate problem, tutorials and Google are my best quick learning tools. Keeping up with other things I tend to watch things like the Discovery & History channels, and read about things I'm interested in. If something isn't interesting to me, or isn't a necessary knowledge to have in this day and age, I usually skim it or ignore it completely.