Public school systems tend to pay well for people who majored in early elementary education, music, kinesiology, etc. But this isn't the same demographic that would work at NSA.
My mom has a master's in education, and after 30 years across two public school systems, she's finally broken $40k salary. Where do you live that public school systems pay well?
Presumably England, where 'public' schools are what would be termed 'private' or fee paying schools in the USA ;)
In Cincinnati, not a particularly HCOL place, with 30 years and a master's she would have made $77k.
Is that really "paid well"? 30 years and a masters degree earns you $77K? Could you imagine that offer in SV?
Cost of living is much higher in San Francisco/Sunnyvale vs Cincinnati. I'm saying $77K in an area where you could get a 3 bedroom/2 bath house for under $200K is pretty good, especially if you don't have the skills to compete in the tech realm, which is about the only way you're going to end up paid well in SV.