Spend some time in a classroom with Korean students and after a while you will notice something that they carry in their pencil cases. Not every kid will have one but most will, especially those in Middle or High school. Kids here carry 'box cutters' in their backpacks. The first time you see one, it comes as a bit of a shock as quite obviously, this would never be seen in the UK. I'm sure some of the kids couldn't be trusted with such a thing. None of the students I teach at my academy need this in their pencil case but many have it. They don't use it as a weapon, they don't mistreat it but still it is often there. By the way, this boys 'cutter' was huge.