Why is it Always High School?

[SouthernBreeze]

First off, I graduated in 1996 so it's been quite awhile since I was in high school, but I still have the same reoccuring dream all these years later.

I'm in high school. Although my actual high school experience wasn't all that great, in the dream I seem very happy and well-adjusted. It's the last day of the year, and I feel great because I know I'm going to have A's on my report card. I'm cleaning out my locker when I find a book at the main bottom under a bunch of papers. I realize it's a book for a class that I had forgotten about even having and haven't been to since the beginning of the year. I panic and hurry to the class. Desperately I try to explain the situation to the teacher, but she says she has to give me an F because I didn't go to class. I feel incredibly disappointed and even a little frightened. Typically the dream ends with me begging to do some special homework or assignment to get a better grade.

The one thing that confuses me about the dream is that it's always high school. I never have a similar one where I'm in college.