Talked on the first day to my students about externalization of motivation, or the overjustification effect: getting external rewards for something that we enjoy can reduce our enjoyment. When we are paid (in money or other commodities) to do something, we often shift our motivation from within ourselves to the reward system.
My general spiel is that students have been subjected to this for 12+ years in the form of grades. Kids are generally curious and delighted to learn. I'm convinced one reason why this changes into the dull-eyed stare in many college students is because they have been graded for demonstrating their learning for over a decade. Grading their academic work (among other dynamics) has shifted their intrinsic drive to learn toward grades instead of the learning itself.
It is very difficult, in this context, to keep one's love of learning alive.
en.wikipedia.org/wiki/Overjust…
Edit: syntax & wording
