<p>I did not take the time to go through every post. But if your S wants to teach down the road, he should look at the number of positions available each year. Harvard Math PhD’s have ended up teaching HS because of marketing conditions. There is a wide disparity regarding job opportunities in teaching among disciplines. For example, currently there are generally fewer PhD’s in business produced every year, relative to the need for college teaching. Yet within business Finance is one of the top discipline in terms of jobs and salaries. I would think this through so I was not surprised at the end of an arduous program. Good luck.</p>