Nick, I think education works very differently here.
In most states teachers are required to gain X amount of post college credits dealing with their subject each year in order to keep teaching. You often are required to pay for these college credits out of pocket and you are rarely reimbursed the full amount (hence the true unfairness in the salaries). While it was the case some time ago that you could get a bachelors or an equivalent and coast on that knowledge for the rest of your career, most states now require this extra learning,
plus a masters or a solid start on obtaining a masters.
Also, Private Schools will often pay their teachers considerably less than a public district. The reason is income tax based government funding. However things like Charter schools pay somewhere in between the two.
The reason people flock to private schools is because they are looking for that distinctive listing on their resume, the kids are usually calm (generally) and you are rarely denied materials for your classroom (because of tuition).
Canaan is really a rich public school district.
As for "evidence" - I dont know if 13 was talking about professors, but I assumed she was talking about primary and secondary educators (as she did mention "kids") of which do not make those salaries and the salaries are entirely based on district, but overall are between 27K and 45K in the east coast urban areas.
Edited: Upon checking the same website:
Median annual earnings of kindergarten, elementary, middle, and secondary school teachers ranged from $43,580 to $48,690 in May 2006; the lowest 10 percent earned $28,590 to $33,070; the top 10 percent earned $67,490 to $76,100. Median earnings for preschool teachers were $22,680.
http://www.bls.gov/oco/ocos069.htm#earnings