Translating Evidence into Improvement
Translating Evidence into Improvement

We Need Experienced Teachers

April 23, 2012

By Pam GrossmanProfessor of Education, Stanford University

From Bill Gates to Arnie Duncan to Michelle Rhee, there's a lot of talk these days about what to do with our nation's teachers: Evaluate effectiveness. Raise salaries. Get rid of tenure.

What we hear less about is keeping teachers in the classroom long enough to make a difference for their students. Teaching is at serious risk of becoming nothing more than a short-term, public service opportunity.

If we want to build an education system built to last, we need to prepare teachers for the long haul and support them in staying in the classroom. By treating teaching as a revolving door occupation, we shortchange both our students and our society.

At a time when we know it takes roughly 10,000 hours to develop expertise, close to 50 percent of teachers are leaving the classroom within the first five years of teaching, well short of those 10,000 hours. And in high poverty schools, where students benefit even more from high quality teaching, teachers are even more likely to exit quickly.

In fact, in the decade between 1997 and 2007, the typical number of years of experience for teachers in the United States dropped from 15 years to just one year. In Washington D.C., following the reforms implemented by Rhee, the proportion of new teachers rose sharply, to nearly a quarter of the teaching force in several of the wards, according to a report in the Washington Post. These are stunning statistics, especially since studies have shown that first year teachers are less effective than their counterparts.

In some ways, this cultural shift in teaching is a return to our past.

In the previous two centuries, teaching was often seen as a temporary occupation. Becoming a teacher served as a vehicle for social mobility for the individual, opening up higher education for women and African-Americans at a time when few other occupations were open to them. No attention was paid to how temporary teachers affected students. This perspective held through the 19th century, and teaching continued to be a short-term job for most. Since teachers were not allowed to be married in many places, women would leave to raise families and men would leave for better paying jobs.

Today, though, we know that high teacher turnover is bad for students.

A new study produced jointly by researchers at the University of Michigan, Stanford, and the University of Virginia indicates that student achievement is negatively impacted by high teacher turnover. The study looked at students in New York City schools and found that student achievement in math and English in grades 4 - 6 was negatively impacted by high teacher turnover. This effect was particularly strong in schools with more low-performing and African American students. Even when a student's own teacher did not leave, the churn of teacher
turnover negatively impacted overall achievement across the school.

Some might argue that keeping teachers in the classroom is not a priority. In fact, programs like Teach for America focus on attracting the most talented college graduates into the classroom in order to prepare leaders who understand the challenges of public education not to prepare career teachers. Yet the high attrition from programs like Teach for America hurts their overall effectiveness, according to our research on pathways into teaching in New York City.

The current research on the effect of teacher turnover on students makes it even more imperative that we focus on ways to keep teachers in the classroom longer, especially in high poverty schools. In fact, Teach for America recently launched a new program called Teach Beyond 2 to encourage their corps members to consider staying in the classroom beyond their initial two-year commitment.

The crossroad is clearly marked. We can invest in the development of highly skilled and well-prepared teachers and create incentives and working conditions to keep them in the profession. Or we can continue to fill schools, particularly high poverty schools with students most in need of high quality teaching, with short-term teachers. To pursue the latter path would only increase the disparities in educational opportunity and achievement that are growing in our society.

So in all the talk about teachers, let's talk more about supporting teachers to help them stay in the profession and improve their craft. As one bumper sticker reads: You can't put children first if you put teachers last.

CEPA Publications

Researchers and policymakers often assume that teacher turnover harms student achievement, but recent evidence calls into question this assumption. Using a unique identification strategy that employs grade-level turnover and two classes of fixed-effects models, this study estimates the effects of teacher turnover on over 850,000 New York City 4th and 5th grade student observations over eight years. The results indicate that students in grade-levels with higher turnover score lower in both ELA and math and that this effect is particularly strong in schools with more low-performing and black students. Moreover, the results suggest that there is a disruptive effect of turnover beyond changing the distribution in teacher quality.