There is a nice line in Judith O'Reilly's book (the doing good one) about teachers, and healers and rescuers. It's tricky to take it out of context without losing meaning, but I'll try. She talks about the idea of doing good being important in life, and ends the 27 Feb entry with this:
"Do those who believe in the critical importance of doing good for their fellow man carry that belief through to the choice of their job? I find that uplifting, that those in jobs that heal us or teach us or rescue us aren't just taking the pay cheque at the end of the month, but that every day they walk the walk with or without a turban and a sword at their side."
The references to the turban and the sword are via Sikhism, in which apparently the men's turban "acts as a sign of disciplined holiness ... while the sword represents the call to uphold justice and protect the weak."
Nobody becomes, or stays, a teacher just for the money. She's right about that.