There is two sides to this equation. Men need to be taught to express their emotions, but society needs to be taught to be just as accepting of a man who expresses his emotions as one who is stoic, if not more accepting. As it stands, you can teach men to express their emotions all you want, but as long as the stoic man is valued more, we are going to have problems.
Part of the issue is the question of who moves first - individual or society. A man who expresses his emotions, in a society where this is not valued or honored, is going to lose social status. I would not want to teach my son to be that "first man" and take that risk.
Additionally, the specific emotions being expressed matter a lot. I would lose a lot more respect for a man if I saw him crying inappropriately in a business situation (assuming the situation didn't warrant it) as opposed to if I saw him get angry and shout inappropriately.
