Graphic/pop art

I used to do a lot of graphic art/drawing/doodling but I haven't had the inspiration in a few years. It seems I always did my best work while in science class in high school - isn't it funny how that works? I wish I could hire a boring teacher to drone in the background so I can be excited about drawing! Here are some examples of various ages. 

 <-- Anyone who can guess what this little guy is is my hero!