From my own experience, I can attest to the differences in student motivation based on age. As an undergrad right out of high school, academics were not my top priority. I was like most 20-year-olds in college: the social life came first. My grades were well below what I was capable of, and this became even more evident during my junior year when my father became terminally ill. My grades improved dramatically as I took more serious approach to life in general. I never imagined myself in grad school, and it was about 15 years before I went ... the first time. I maintained a 4.0 through much of it, and actually felt it ws a burden in some ways, because, while i had it I wanted to keep it. I fell a little short, but completed an MBA with about a 3.8. A few years later I went back for another Master's, this time in teaching. Same situation, a 4.0 for the first semester or two. It was a relief in some ways to get a B. I finished with about a 3.93. As an undergrad, grades were almost an afterthought. As an adult, I was driven to succeed. This applies to many -- though certainly not all -- students in these two age groups.