When reading Bruce Lee's notes it is clear that he was a firm believer in placing the strong side forward. 90% of our striking should be done with our strong hand and our strong leg. The reasons are two fold. First, because our lead hand is closer to the opponent it will reach its target that much quicker. Second, Since the dominant hand is forward one is able to hit the openings as soon as they appear.
One way to teach is through basic front hand education. Basic front hand education is a series of punching combinations all done with the lead hand. Since the student is only punching with the front hand it gets them more comfortable with punching solely with the front hand and with constant reinforcement the student will also be able to generate power behind his lead hand punches.