Education News Colorado rounds up last night’s school board races. And in purple CO raising taxes for schools doesn’t seem to go over well right now.

Ed Note – This week Eric Hanushek and Diane Ravitch are discussing whether removing the lowest-performing teachers is a good idea.  Hanushek started the debate on Monday and Ravitch responded yesterday. Here’s Hanushek’s response below.   Ravitch will finish the conversation with a post tomorrow.

By Eric Hanushek

Diane comes back to a simple prescription:  We should pursue business as usual with a few extensions of current policy.  Unfortunately that is not serving us well, because this is exactly what we have done for several decades.  We have developed a system that pays little attention to students and their achievement but that supports any adult who has found a job in schools.  This policy does not look good by historical evidence on student outcomes.  But it is common to defend this basic lack of management by throwing in red herrings whenever any policy change is suggested.

Once more through the evidence:

We have clear and consistent estimates about the variation in teacher effectiveness that exists in schools.  The information comes from information on student test scores – something that is directly related to future student earnings and to the aggregate performance of the economy.

Differences in skills on tests of math, science, and reading lead to stunning differences in economic outcomes.   Economic outcomes are not everything.  But, as we have a continued national debate about both our international competitiveness and the fate of the bottom of the income distribution, we should not ignore economic outcomes.

Undoubtedly other, unmeasured things beyond test scores are also important to students and to society, but there is no reason to believe that being good in these other things is hurt by having greater measured skills.  And there is no reason to believe that teachers at the bottom in terms of producing measured skills are anything but the bottom in producing useful unmeasured skills.

It is a red herring to say there might be unmeasured other things that are also important.

Further, there is now consistent evidence that ratings by principals (on metrics other than test scores) are highly correlated with ratings on test scores at the top and bottom of the distributions.  While there is confusion in the middle, there is not confusion at the top and bottom.

It is a red herring to say that different evaluation systems produce different results.

If we put together the impact of good teachers on student achievement and the impact of achievement in the lifetime earnings of students, we find that a good teacher (one in the top quarter in terms of effectiveness) each year produces over $350,000 more income for her students compared to an average teacher.  But, symmetrically, a teacher in the bottom quarter subtracts $350,000 in income each year of teaching compared to an average teacher.

Ignoring these differences leads to huge inequities and to enormous waste in the potential of our students.  I personally think the stakes are large enough that we should consider something other than business as usual.

As Diane points out, I have always advocated other policies that support the improvement of our teaching force: better mentoring, improved professional development, well designed curricula, complementary technologies, and so forth.  But, my interpretation of the evidence is simply that none of these policies has been very successful at improving the least effective teachers.  Further, our “best” teacher development policies do not go to scale up very well and are not systematically chosen by districts.

It is a red herring to point to other, complementary policies for improving teacher effectiveness without acknowledging the importance of starting with effective teachers.

Finally, it is fine to talk about teacher turnover, but not all teacher turnover is bad.   If we move a bad teacher out of a school serving disadvantaged students, it is not a bad thing.  The turnover  rate in teaching is no different from that in other professions, and the initial turnover in teachers should not be used as a reason for ignoring the effectiveness of teachers.  There is an excess supply of potential teachers.  The shortage is not teachers per se but effective teachers.

It is a red hearing to say that teacher turnover is high without considering the implications for teacher effectiveness and ultimately for  student achievement.

It is unfortunate that the “applause lines” to which Diane gravitates tend to be red herrings, distracting us from the national imperative to improve the effectiveness of our teacher force.  I have focused on one specific policy – eliminating the teachers that are harming our children.  Diane wants to introduce the idea that, while there are teachers who are harming kids, we should not deal with them because there might be some residual uncertainty about the very last teacher who is in this group.

She repeatedly use the word “firing” to conjure up images of large, unjust, and arbitrary actions.  To the contrary, it is simply good management to move a very small number of ineffective people out of the front line of schools.  And by so doing, it acts to elevate the status of the vast majority of effective teachers.

Policy by red herring seldom leads to good policy.  It certainly does not when considering teacher policy.  Diane is very skillful at distracting us from issues of student achievement, but avoiding those issues will be very costly to the nation.

Whether you’re short or long on Netflix or don’t even like movies at all, don’t miss this edgy post by Neerav Kingsland.

Ed Note – Yesterday in a post below Eric Hanushek argued in favor of removing the lowest-performing teachers. Today, Diane Ravitch responds below.  Hanushek will respond tomorrow and Ravitch again on Thursday.

By Diane Ravitch

I had the pleasure of working alongside Eric Hanushek for a decade as a member of the Koret Task Force at the Hoover Institution. During that time, we had many opportunities to discuss these issues.

Rick claims that we are not eliminating enough teachers; that if we fired the “bottom” 5-10% of teachers, our national performance would rise to the top of the world. He assumes that a “low-performing” teacher would be replaced by an average teacher, thus leading to a drastic overall improvement in student outcomes.

Nobody disagrees that there are ineffective teachers and that, if they are unable to improve, they should be removed. But let’s clear a few things up.

When Rick says “research shows” that removing the “bottom 5-10” percent would generate dramatic results, he is referring to his own calculations, not to any actual program that has ever been tried. It’s a hypothetical extrapolation, and it consists of removing teachers based solely on test scores. Rick says he doesn’t advocate for purely test-based dismissals. But the dramatic improvements he foresees are based solely on students’ test scores.

Even in a perfect world where all the assumptions of his calculation hold up, we have very little idea of what the distribution of teacher effectiveness looks like when that effectiveness is measured using an evaluation system comprised of multiple measures. Different measures, such as observations and value-added, measure different things. The “bottom 5-10 percent” on one measure are not necessarily the “bottom 5-10 percent” on another.

At best, Rick’s calculation illustrates that there are more and less effective teachers, about which there is little disagreement. But there’s a difference between trying to show that teachers differ in their abilities and saying that firing people based on a criterion that nobody supports will produce huge results in the real world.

Rick “assumes away” many of the biggest issues. He seems confident that brand new evaluation systems can identify the “worst” teachers in a manner that is accurate enough for us to fire them based on those scores. A teacher ranked “ineffective” one year might be “effective” the next year, and this might happen often enough that we end up firing many good teachers.

Rick assumes that the teachers who are fired will be replaced by “average” teachers. But that is just an assumption. They are even more likely to be replaced by teachers in their first year of teaching, inexperienced teachers who need intensive support and training. Attrition in many high-poverty schools and districts is already at a critical mass. How will these schools manage under a system of ongoing, annual layoffs?

I would like to disagree as to the larger idea that firing teachers is the key to fixing U.S. public education.

The problem, Rick believes, is that we are not firing enough teachers. The problem, as I see it, is that we are not doing enough to recruit those who are well prepared and then supporting them once they are in the classroom.

At present, we have a very inefficient means of recruiting teachers. In many states, people may become teachers with little or no preparation, and they get little support once they are in the classroom. In addition, attrition is huge. Overall, some 50 percent of new teachers are gone within five years. In poor and minority schools, the percentage leaving may be even higher than 50 percent.

Among the 50 percent who leave teaching are surely many who were fired or who realized that they weren’t good at teaching. Rick’s own research finds that the teachers who leave tend to be less effective than those who stay. But many other good teachers leave because they are discouraged by the working conditions (lack of supplies, mentors, poor leadership, physical conditions, etc.)

I think we should take steps to raise entry standards, provide strong on-the-job training and support, and improve the retention of those teachers who make it through the first three-to-five years.

It is hard to see how Rick’s proposal would improve education or the teaching profession. Why would people line up for a job that is poorly paid and under constant attack, where working conditions are often abysmal, where the teacher is often expected to buy essential supplies out of her own pocket, where pensions and healthcare are being whittled away, where class sizes are rising, where librarians and social workers are laid off, and where support is minimal or nonexistent.

Elsewhere, Rick writes that (pdf), “in the long run, it would probably be superior … to develop systems that upgrade the overall effectiveness of teachers.” He worries that efforts to improve the quality of teachers, such as mentoring and professional development, have not thus far been successful, so he prefers what he calls “deselection.” I don’t think we should give up on efforts to improve the profession.

Given the already high turnover of teachers, given the low respect that teachers today command, given the need to develop a large number of well-prepared, skilled, experienced teachers, I maintain that we should improve the recruitment, support, and retention of teachers. We should aim to build the profession, not to make it more insecure and less professional. Other nations have improved the teaching profession by strengthening it, not by annual firings. So should we.