Although many personal, family, and neighborhood factors contribute to student academic performance, research demonstrates that, among school-related factors, teachers matter the most. Thus it makes sense for lawmakers to look for ways to improve teaching effectiveness as part of efforts to reauthorize the Elementary and Secondary Education Act (ESEA). Equally important, any approach Congress considers should take into account the strengths and weaknesses of different ways to measure and promote effectiveness, and their implications for policy aimed at providing the most effective teaching possible to every student.
Across the country—even within districts and schools—there is a wide range in teaching effectiveness. There is also a wide range in the ways teaching quality can be measured, including the academic qualifications of teachers, their instructional practices, the achievement gains made by their students, their contribution to the school community, and the experiences and satisfaction of students and parents. Given this context, policymakers designing an evaluation system must take care to consider the benefits and limitations of each method, particularly if the system has serious consequences for teachers.
One method that would seem to offer an obvious choice for measurement is Value-Added Modeling (VAM), which attempts to measure a teacher's impact on student achievement over time—separate from the student's individual ability, family environment, and past schooling—by focusing on student improvement from one testing period to the next. Because they use standardized test scores, which provide an efficient, objective way to measure student learning, VAM and similar statistical models sound like a promising technique. However, they face several limitations. Different methods of computing a VAM score can produce divergent results, raising questions about the accuracy of each approach. Additionally, the accuracy of many of these models depends on random assignment of students to teachers, when in fact parents, school leaders, and others often play a role in assigning teachers to students. Furthermore, most teachers don't teach a grade or subject in which a state or district test is administered, and VAM requires consecutive-year test scores from the same students. Locally developed tests used by some schools are typically less reliable than large-scale professionally developed tests. While VAM can provide important information about a teacher's performance and contribution to student learning, its drawbacks should limit its use as an exclusive measure of teaching effectiveness.
Among other evaluation techniques, classroom observation—the most common method of measuring teaching effectiveness—directly measures teaching practices, providing educators with specific feedback about particular aspects of their instruction. While training administrators to use carefully designed rubrics can lead to reasonably reliable and accurate judgments about teaching practices, these activities usually require more time and money than test-based approaches. Surveys of parents and students, and examining teachers' knowledge or skills and participation in professional development can also shed insight on teaching effectiveness, however, more research is needed to fully understand their impact and effectiveness.
Given these various concerns, we recommend that Congress address the following points related to evaluating and promoting high-quality teaching when considering the reauthorization of ESEA:
Congress should encourage states and districts to adopt high-quality teacher evaluation systems that rely on multiple measures. A combination of measures that includes student achievement growth, classroom observations, and other information such as student feedback surveys can increase the utility of information from evaluations and decrease the likelihood that teachers will be inaccurately classified as low performing. Given teaching's complexity, it would be inappropriate for states or districts to make high-stakes decisions about teachers on the basis of any single measure.
Teacher evaluation systems should be designed to support instructional improvement. One of the most promising aspects of new teacher evaluation systems is their potential to help teachers, and those who supervise them, identify teachers' strengths and weaknesses rather than simply labeling teachers as high or low performers. Measures that provide breakdowns for specific aspects of teaching, such as rubric-based classroom observations, are more likely to be informative than are measures that gauge effectiveness only in broad terms, such as VAM.
Professional Development (PD) should be targeted toward the needs of individual teachers. More detailed and informative teacher evaluation systems can help teachers and their supervisors identify PD opportunities that address their needs, and it is essential that district and school leaders ensure that appropriate PD is available and that teachers have the resources (including time) to pursue them. The current Title II provisions that emphasize increasing the percentages of teachers who participate in PD have led many districts to emphasize quantity rather than quality. High-quality PD not only addresses teachers' needs but also encourages them to try out new instructional strategies, reflect on their practices, and receive feedback from colleagues and mentors.
Professional development should also be provided to school leaders to help them better evaluate and support teachers. While teachers produce the strongest school-based influence on student achievement, school principals are critical in supporting conditions for effective teaching. Principals and other school leaders play a key role in conducting teacher evaluations, providing feedback, and creating the conditions necessary for teachers to pursue both formal and informal PD opportunities. Many school leaders lack the training and skills to carry out these duties effectively, therefore, efforts to improve teaching should not neglect the need to improve school leadership.
Policies aimed at boosting teaching effectiveness are a key component of a strong ESEA reauthorization. Addressing discrepancies in teacher quality goes far beyond identifying good and bad teachers: It helps teachers improve, retains effective teachers, and makes the teaching profession an attractive option for those contemplating careers. These policy recommendations can help Congress set both new and veteran teachers up for success.
Laura Hamilton is a senior behavioral scientist, Brian Stecher is a senior social scientist, and Grace Evans is a legislative analyst at the nonprofit, nonpartisan RAND Corporation.
Commentary gives RAND researchers a platform to convey insights based on their professional expertise and often on their peer-reviewed research and analysis.