While I am sure there are local variances, a high school teacher in my neck of the woods will easily out earn the typical web developer by a sizeable margin. I cannot begrudge someone for doing well in their career, but there is a sentiment found in this thread, and I am under the impression that you are alluding to the same, that higher paid teachers will produce better outcomes for the students. I am not sure there is in any indication of that being the case.
Purely anecdotal, but I was a tutor for two years out of college and planned to be a teacher (originally college, then high school). I went into a different field for 3 reasons:
1. Pay
2. Professionalism - all of the teachers I saw and talked to under 65 were treated like dirt, and were micromanaged instead of being treated like professionals
3. Barriers to entry. By the time I got my Master's and decided I'd rather teach high school than spend several more years getting a PhD, it was financially impractical for me to go back for more years to get a teaching degree. It was also very difficult to find internships and open positions. One guy I know who did a straight teaching degree interviewed almost a HUNDRED TIMES despite doing incredibly well in his program and student teaching at a prestigious high school.
I'm sure the kids are doing fine without me, but I had stellar reviews from every kid and parent I ever worked with, and from professors I TA'd for. People have told me my whole life I should be a teacher (came up again just the other day with the guy I was pair programming with). I'd happily take less money to be a teacher, but when you add in factors 3 and especially 2, it just isn't worth it to me. I'm not going to suffer a bunch of professional abuse and take a financial hit to boot to do something that my society doesn't seem to genuinely value.
I don't know where you're located, but in the U.S. if you already have a masters, you don't really need a teaching degree (a certificate is all that is needed in most states). My wife, an eighth grade science teacher, has a masters in neuroscience - no formal teaching degree - and is on the same payband as any other teacher with a masters.
I see your second and third points being issues locally as well – if you work for the government.
However, you might be interested to know that the most successful business in my neighbourhood actually operates an online high school. A friend of mine in another city also operates an online high school and seems to be doing quite well for himself. There appears to be a large market for such services.
Especially if you also have web development skills, the internet provides a platform to be a teacher independently, resolving the second and third points. The first point probably depends on your business skills. However, seeing how well that aforementioned business in my neighbourhood is doing, the potential upside is huge.
