Being yelled at can be a trigger for some people. I don't know where this kid is coming from-but its entirely possible that being yelled at has become synonymous with about to get beaten.
It's also entirely possible that this was just the final straw in an series of difficult and stressful events.
It's been my experience that people cry for two main reasons. 1. Because they have a lot of emotion/stress and crying is the means they are using to cope (even if they don't want to be crying). Or 2. Because crying has proven to yield useful results for them historically. (To manipulate people) since this is a high school aged boy, I would guess the former, since crying tends to only result im n mockery from others when you are a boy after a certain age.
It's also entirely possible that this was just the final straw in an series of difficult and stressful events.
It's been my experience that people cry for two main reasons. 1. Because they have a lot of emotion/stress and crying is the means they are using to cope (even if they don't want to be crying). Or 2. Because crying has proven to yield useful results for them historically. (To manipulate people) since this is a high school aged boy, I would guess the former, since crying tends to only result im n mockery from others when you are a boy after a certain age.