Drawn using only straight lines

I used to draw stuff like this while taking notes in skewl. It's relaxing.

i remember in like 3rd or 4th grade, we were given the task to draw a picture with only straight lines, i did a parrot, using very short lines, like 2-5mm. This girl, who thought she was the teachers pet, started to complain i was drawing with curves, until the teacher pointed out i was still using straight lines.