Many years ago I worked in a group home for troubled kids.
One night during dinner I was having a conversation with one of the kids when another kid asked me a question. I turned to answer the other kid and the first one, feeling disrespected, bounced her Melemene dinner plate off my forehead. That was the beginning of my journey of learning situational awareness.
I also worked in a mental health facility for almost a year. That was an environment where one minute a patient was fine and the next he decided that you were the Antichrist and you had to die. That only has to happen a couple of times before you really start paying attention to what's going on around you.
I honestly don't know if you can teach somebody situational awareness any other way than by putting them in a position where they have to pay attention to what's going on around them or they're going to have to suffer actual consequences.