I took a couple of art classes in college. I wasn't very good, but we had to do a charcoal of a living model. She didn't take her clothes off. It was a 101 level class. But I did get her shape right and her position, and I was even thinking I had done a particularly good job, although I could never draw a face, except for maybe the smiley face icon. So I just drew the shape of her head, and left the face blank. But it still looked OK to me, like the face was left blank for artistic effect, rather than as evidence of incompetence. It was done on one of those large size pads like the ones in PickelledEggs' photos. When I turned in, I managed to tear off a corner, but the drawing was still intact.
Later, the art department had a student art show, and I was surprised to see my charcoal on display. It was just stapled to a huge display board in amongst a bunch of other paintings, sculptures, etc of other student's work, still with the torn corner, like it was a throw-away, but something the art department salvaged from a pile of discards.