New Evidence Points to the Importance of Teachers’ Colleagues

Written by: Amy Auletto

Primary Source:  Green & Write, March 6, 2017

Who we work with matters. In many professions, we often work closely with our colleagues on a regular basis, building professional and personal relationships, collaborating on projects, and serving as one another’s support systems in the workplace and beyond. This is especially true for teachers. Teachers work together formally, in grade-level teams and professional learning communities (PLCs), as well as informally. If a teacher needs to leave her classroom for a moment to speak with a parent, a colleague may step in and watch her class. If a particular lesson didn’t go well, another teacher in the building might suggest different ways to teach that concept. If a student is struggling with her behavior, perhaps the teacher across the hall can provide a brief change of scenery for that student before things escalate.

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Research on teacher collaboration has demonstrated that there are tremendous benefits when teachers work together. A 2015 literature review of teacher collaboration identifies a number of ways in which students, teachers, and schools as a whole benefit from teachers participating in PLCs or other teacher teams. Student learning is improved when teachers learn new instructional strategies from each other. Teacher morale, motivation, and efficacy are higher; teacher attrition rates are lower; and teachers develop leadership skills. At the organizational level, school climate and culture are also improved.


Teacher Spillover Effects Benefit Students

A new study, however, suggests that colleagues can also benefit each other outside of formal teacher collaboration activities. Researchers Min Sun, Susanna Loeb, and Jason Grissom studied teacher transfers in grades 3-8 in Miami-Dade County Public Schools. They found that when a particularly effective teacher transfers to a new grade-level, all students in that grade have improved learning outcomes, even those that the new teacher does not directly teach. Researchers often refer to this phenomenon as a spillover effect. Sun and her colleagues found that the spillover effect of a strong teacher joining a grade-level team leads to an additional 25% boost in student achievement scores. Fortunately, this study did not find the opposite to be true. That is to say, if a particularly ineffective teacher transfers to a new grade-level, he or she does not drag down the test scores of other students in the grade.


Implications for Teacher Evaluation

Because effective teachers provide benefits to students outside of their own classrooms, school leaders can make strategic decisions as to how to most efficiently disperse their strongest teachers in order to maximize student learning and strengthen the practices of other teachers in the building. Relative to more costly approaches to instructional improvement, such as professional development, strategically placing strong teachers is certainly an affordable strategy to boost student achievement.

The findings from this study, however, raise some serious questions related to teacher evaluation. While formal teacher evaluation systems vary across states, they all tend to place a significant emphasis on student learning. In Michigan, for example, student growth and assessment data account for a substantial portion of a teacher’s year-end effectiveness rating, which has implications for licensure and dismissal. Yet if a considerable portion of a student’s learning can potentially be attributed to other teachers that are not directly working with that student, then just how accurate are our current approaches to teacher evaluation? Two teachers may otherwise perform at a similar level but if one of these individuals happens to be placed in a grade-level with strong teachers and the other does not, these two individuals will potentially receive different effectiveness ratings at the end of the year due to no fault of their own.

While this new evidence of teacher spillover effects has the potential to inform the assignment of teachers within schools in ways that can maximize student learning, the implications for teacher evaluation must also be considered. We need to make sure that teacher evaluation practices are not unfairly advantaging or disadvantaging teachers based on who their colleagues happen to be.

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Amy Auletto
Amy Auletto is a doctoral student in Educational Policy. She is interested in the impact that equitable funding and access to effective teachers have on the educational outcomes of disadvantaged student populations. Prior to beginning her studies at Michigan State University, she taught middle school math in Detroit. Amy earned her bachelor’s degree in psychology, master of Social Work, and MA in educational studies from the University of Michigan.