Coming to the civil rights movement in the twentieth century, we begin to have this idea that's still with us today, which is that the main purpose of public education is closing achievement gaps.

A lot of charter schools are non-union schools that take a lot of teachers from alternative tracks, like Teach For America. They do this in part because a lot of charter schools have very strong ideologies around how they want teachers to teach. And they find that starting with a younger or more inexperienced teacher allows them to more effectively inculcate those ideas.

I wrote a work of history, I looked at over 500 sources - I spent three-and-a-half years on the project. I think the most gratifying and wonderful thing about the reaction is that people are learning things from the history that feel relevant to today.

Younger teachers are definitely more likely to have worked at charter schools as opposed to have just heard of them. Charter schools explicitly look, often, to hire younger people. I've even talked to people who didn't necessarily go into teaching thinking they wanted to work at a charter school or even may have been considered critics of the charter school movement, and found that it was the only way for them to get their foot in the door. So young people just have much more familiarity with the concept.

Teaching is been seen as kind of a moral calling and not as an intellectual job.

Men are more salary-sensitive when they're choosing a job.

We have a lot of rhetoric today about "high rigor" and you often hear terms like that thrown about when discussing the Common Core. But the American education system historically has not embraced intellectual seriousness.