The correct answer to this open question is the following.
The behavior I would like to change is my brother's impatience.
From the lesson learned in class, I would use the "positive and negative reinforcement," to help him change his conduct.
One of the bad habits he has to change is that he gets desperate very quickly when things don¿t work his way. And that has been a real problem for him, specifically in school and with his relationships.
He also has good habits but what he needs to immediately do is to improve his study habits because he is a slow learner. That is one of the reasons he has no patience.
I would like the behavior to change by letting him understand how his impatience has only brought negative consequences. The strategy I will use is to paint a clear picture in a bow, with all the things that he has generated for not being patient. And all the people he has hurt when he screams and shouts in despair. I will make a list of the friends he has lost because he can't control those difficult moments.
I think it will take a couple of months to start changing his behavior because when he calms down, he realizes the number of people he has hurt and the damage done.