I used to have dreams with variations on the theme of somehow failing in college or forgetting about a class and not showing up for it until most of the semester was over.

I haven't had those dreams for a while now.

I don't really think about dreams that much, but I don't ignore them either. Mostly I don't remember the details of my dreams after I wake up, with a few rare exceptions. I do remember general feelings or scenes, and sometimes they are called to mind during the waking hours. One of those, "did that happen, or did I dream that?" moments.