When I was in 2nd grade, my teacher was reading a story to the class. I got bored and wanted something to occupy myself, so I tied my shoelaces together so I could then take them apart. I kept dong this, making the knot tighter and more difficult to undo, until I couldn’t actually get them apart. When the story was over, I had to ask the teacher to untie my shoelaces, and had to sit at my desk for some tie with no shoes on.