Unhappy with your current salary? Maybe you can blame your teachers.

Based on what we know about the effects of teacher quality on student achievement, as well as what we know from research showing that students who do well on tests end up earning higher salaries, economist Eric Hanushek estimates that an effective teacher instructing a class of 20 students may generate as much as an additional $400,000 in future student earnings every year.

Looking at the big picture impact of student performance on economic growth, Hanushek estimates that if we reduced by half the gap between student performance in the U.S. and in top performing nations like Finland and Canada, the U.S. economy, not just our kids, would be the great beneficiary, adding another $44 trillion to our productivity.

The good news is that no matter how you cut it, there are huge economic gains to be had by improving teacher quality.

The bad news is that even though we know that teachers are the most important school determinants of student achievement, most of the policy initiatives aimed at teachers fail to address the most effective way to get results.

Hanushek takes on the many ineffective ways in which the U.S. spends money to improve student performance--smaller class sizes, degree-based compensation for teachers, experience--and few of these strategies will have any impact. That means we're still not making the profession any more attractive to top candidates and we're not doing enough to weed out ineffective teachers. If we were to replace even the lowest performing eight percent of all teachers with an average teacher (not even a highly-effective teacher), the U.S. would end up on par with top performing countries.

If schools continue to shirk their responsibility to move ineffective teachers out, Hanushek offers another idea. In a twist on conventional wisdom (where the best teachers are rewarded for their performance with smaller classes), he suggests minimizing the negative impact of ineffective teachers by letting them teach the smaller classes, earning considerably less money for the privilege, allowing schools to get the biggest economic bang for the buck out of their best and brightest teachers. If the approach doesn't help address the teacher effectiveness problem, it might at least reduce the clamor for access to smaller classes.