Is the system setup to value them with money? Can a parent walk into a school and agree to higher property taxes if their kid is placed in a specific teacher's classroom?
Male teachers face the same issue. But really, salary is only one component of what they are paid.
Just about any teacher that survives to an old age will beat me earnings wise with their pension, which they don't have to fund. I have to fund my own 401K or IRA, as well as pay into the teacher's pension fund with my property taxes.
They're not paid more because their unions negotiate a fixed salary schedule through collective bargaining, and most teachers support this state of affairs. It's hardly a pure value judgment on the part of "society".