Heh, when I was in school, yes. In earlier grades, I probably did it too much, keeping me from paying attention in class. Then in college, it was just something that I did in my spare time. But you know, I love looking at those drawings from grade school to college... I made up my own characters and as my drawing abilities improved, so did my characters; so it is a lot of fun to look back at my old drawings.
They went beyond doodles that sat innocently at the side of my homework page, I would also make comics out of these characters whenever I had some time on my hands. In college, if I had trouble understanding something in a particular class, I would make a short comic about it with my characters to help me remember.
Those were the days.