Success magazine had an article in the November 2013 issue about "tiny habits." The principle is worth teaching. The basics are:
The article also suggests breaking goals down into steps. For example, your goal is to run everyday; start the first day by just putting on your running close. On the second day put your running clothes and shoes on. On the third day put your running clothes and shoes on and step out the door. And so on, breaking it into small steps daily help to solidify the habit.
Also, don't forget step 3, CELEBRATE IMMEDIATELY, our brains can't recognize when we wait too long to celebrate. By celebrating immediately we are rewarding the behavior in a way our brains recognize.