(CNN) Twenty-five years ago, teaching public school was a pretty attractive gig.

Teachers got to help mold young minds. They mostly had summers off. And they were paid roughly as much as their counterparts in similar professions.

Today, not so much. Teachers in the US earn significantly less than workers in comparable jobs, especially in states such as Arizona, Colorado and Kentucky where educators have been protesting and walking out of school.

And the pay gap is widening.

"Are we really getting our best and our brightest to be teachers anymore in this scenario?" says Sylvia Allegretto, an economist at the Economist Policy Institute who analyzes teacher pay gaps.

Read More