A recent bipartisan report from the National Conference of State Legislators bluntly noted that, “Most state education systems are falling dangerously behind the world in a number of international comparisons and on our own National Assessment of Educational Progress, leaving the United States overwhelmingly underprepared to succeed in the 21st century economy” (“No Time to Lose”, August 2016).
A critical question is the extent to which tenure and other laws that keep poor teachers in America’s classrooms are contributing to our poor K-12 performance.
Over the past four years, four independent studies using different methodologies have reached similar conclusions about the percent of poor teachers that are in America’s classrooms.
In 2014, the Harvard/Education Next Poll asked teachers to anonymously grade other teachers in their local schools. Teachers gave 13% of their peers a D or an F.
In 2015, the Gallup Organization found that 13% of the nation’s teachers were what it termed “Actively Disengaged”, which is defined as follows:
“Actively disengaged people operate from the mindset, ‘I’m okay. You’re not okay.’ They believe that they’re doing what needs to done, and everyone else is wrong. Negativity is like a blood clot, and actively disengaged employees sometimes clot together in groups that support and reinforce their beliefs…”
“Actively disengaged employees also may close themselves off from anyone who will challenge them to become part of the solution, rather than staying part of the problem. This is key to understanding the difference between an engaged and actively disengaged person. An engaged person occasionally becomes negative. We all do. But an actively disengaged person finds it almost impossible to become part of the solution, because they thrive on being part of the problem” (“Lack of Teacher Engagement Linked to 2.3 Million Missed Workdays”, January 2015).
In 2017, Grissom and Loeb published “Assessing Principals’ Assessments: Subjective Evaluations of Teacher Effectiveness in Low- and High-Stakes Environments.” In private assessments, principals rated 15% of their teachers as ineffective (in official assessments, the percentage rated ineffective was much lower).
Also in 2017, David Griffith published a study of “Teacher Absenteeism in Charter and Traditional Public Schools”, using data from the US Department of Education’s Office of Civil Rights. Griffith found that nationally, 27% of teachers use more than 10 personal and sick days each year — 10 days is the point at which OCR’s research says the impact of teacher absence on student achievement becomes significant (to say nothing of its budgetary impact).
A subsequent study examined a range of potential (and reasonable) explanations that had been offered for this high absence rate, and concluded that 16% of these absences could not be explained.
So, across four studies using different methodologies, we have estimates of the percent of teachers who probably shouldn’t be in our kids’ classrooms that range from 13% to 16%.
Other studies have found that the cost of keeping these teachers in the classroom is far higher than most people realize.
In “The Long-Term Impacts of Teachers: Teacher Value-Assed and Student Outcomes in Adulthood”, Chetty, Friedman, and Rockoff conclude that in New York, “replacing a teacher whose VA is in the bottom 5% with an average teacher would increase the present value of students’ lifetime income by more than $250,000 per classroom.” Put differently, keeping a poor teacher in a classroom for ten years generates negative costs to society of more than $2.5 million dollars.
This study was replicated by Bacher-Hicks et all (“Validating Teacher Effect Estimates Using Changes In Teacher Assignments In Los Angeles”), who found that “the heterogeneity in teacher effects was considerably larger in Los Angeles than in New York City. The consequences for math or English achievement of being assigned a top rather than a bottom quartile teacher in Los Angeles were nearly twice as large as in New York.”
In sum, there is strong evidence on two critical points. First, between 13% and 16% of teachers probably don’t belong in America’s classrooms. The most recent data show that the United States has 3.8 million K-12 teachers. Conservatively, about 500,000 of them are probably poor performers.
Second, the negative economic impact on these teachers’ continued presence in the classroom is likely very large — about $125 billion per year (500,000 x $250,000) in present value terms.
So why can’t school districts get rid of them?
The underlying issue is a fundamental and unavoidable tradeoff between a preference for errors of commission (“false alarms”) versus errors of omission (“missed alarms”). Seeking to minimize the probability one type of error automatically increases the probability of the other type.
Teachers’ unions have stressed the importance of minimizing errors of commission — mistakenly dismissing someone who is actually not a poor teacher. Yet this position automatically implies an unacknowledged willingness to accept a very high rate of errors of omission — mistakenly leaving poor teachers in America’s classrooms.
Presumably, parents and employers would prefer the opposite tradeoff, considering the substantial negative impact of poor teachers, both in aggregate economic terms and on individual students’ futures.
Moreover, wrongfully dismissed teachers can find other jobs. Students who have a bad teacher — or even worse, more than one — usually have a far harder time making up the ground they have lost — if they ever do.
Yet thanks to teachers’ unions’ impact on elections, in too many U.S. school districts getting poor teachers out of the classroom remains exceptionally difficult — and each year millions of children, as well as our economy and society, continue to pay a very high and rapidly compounding price.
Tom Coyne is a private sector executive. For 17 years, he has invested all his volunteer time in K-12 performance improvement at the school, district, and state levels.
