First off, I appreciate everyone's comments.

I've read them all carefully, and done a lot of extra reading on my own.
For those that think I'm nuts

for leaving a fairly lucrative career teaching high school physics, I'm considering leaving due to the wildly changing nature of public education. For example, in my current teaching position:
1. physics is becoming a 9th grade, no math, watered down general science class.
2. teachers must teach exactly how and what is in the prescribed program/text, each teacher must do exactly the same thing and give exactly the same tests, there is very little freedom and creativity in teaching.
3. teachers are required to allow students to do test retakes with very few limitations.
4. there are many bad situations with special education where teacher are held responsible if the student doesn't succeed. My current superintendent said that no special education student will EVER fail.
5. the current trend follows the national no child left behind (NCLB) where all students will do well, period!
6. in general, there is very little emphasis on academic achievement.

Instead, there is great attention to covering your butt at the administrative level.
(sorry about the ranting, I needed to get it out)
I would hope to scrape by economically while earning a PhD and then teach at the college level and/or do research. I really do love teaching, but I think the university setting would allow me to concentrate on teaching, and not all the other garbage.
I am going to continue researching my options, talk to some local professors, and hopefully talk to an acquaintance that went from teaching high school to a PhD. I will also look for other high school teaching positions to switch to, but the tough economy typically forces schools to hire teacher right out of college (lowest salary).
Please continue to comment on my original post, or shoot holes in my reasoning.
Thanks