Making a habit of autonomy, mastery and purpose

My differentiated biology class is based on the concept that humans are most powerfully motivated by autonomy, mastery, and purpose--a concept I got from Daniel Pink's powerful book, Drive.

But another powerful book has gotten me wondering lately whether I'm missing something: The Power of Habit by Charles Duhigg.

Duhigg breaks down habits like this: Habits consist of a cue (a trigger, like stress), a routine (like biting your nails or drinking), and a reward (dopamine).

But Duhigg emphasizes that it's really not a habit until you start craving it--until your brain starts expecting the reward every time it sees the cue.

I'd like to help my students form new habits, but at first the idea of habit seemed contradictory to Pink's trinity of intrinsic motivators.

Then I realized how the two ideas fit together:

1. Motivation is a craving. 
2. Autonomy, mastery, and purpose are routines that can produce rewards for your brain (dopamine). 

Some students crave good grades. Others don't.

Some develop the habit of doing their homework. Others don't.

We could focus on teaching them to crave grades and fear penalties, do their homework, and turn stuff in on time.

But I want to aim higher. I want to help my students develop habits of autonomy, mastery, and purpose.

I want to help them crave the reward that comes from those things.

Because that's the essence of intrinsic motivation.