Measuring Teacher Effectiveness FAQ

Teacher helping schoolgirl at school, photo by eric/AdobeStock

Photo by eric/AdobeStock

Measuring teacher effectiveness is an extremely complex and important topic.

RAND Education and Labor's experts have answered some of the most frequently asked questions about this policy issue, providing clear, concise, but rigorous answers.

I know that teachers are important, but exactly what kind of impact do they have on student achievement?

Research suggests that, among school-related factors, teachers matter most when it comes to a student's academic performance. Non-school factors also influence student achievement, but effective teaching has the potential to help level the playing field.

Teachers Matter: Understanding Teachers' Impact on Student Achievement

How can we measure teaching effectiveness?

Teaching is a complex activity that should be measured with multiple methods. Each method has advantages and limitations, so combining measures can provide a more comprehensive and accurate picture of a teacher’s effectiveness than any single measure. Methods that are commonly used in teacher evaluation systems include:

  • Student test scores: Metrics constructed from standardized test scores provide information about the extent to which students have mastered core academic content.
  • Classroom observations: Observations measure teaching practices directly, typically using a structured rubric or checklist that is administered by a principal or other educator.
  • Surveys and other methods: Many school districts and states use surveys to measure students’ or parents’ perceptions of teaching.

Other approaches include tests of teachers' knowledge and skills; documentation of participation in professional development, committees, or mentoring; and input from peers or administrators.

Multiple Choices: Options for Measuring Teaching Effectiveness

What is value-added modeling, and how can it measure a teacher's impact on student achievement?

Value-added models, or VAMs, attempt to measure a teacher's impact on student achievement apart from other factors, such as individual ability, family environment, past schooling, and the influence of peers. Rather than focusing on how students test at a single point in time, VAMs estimate how much improvement they make from one testing period to the next.

Value-added models provide an estimate of the relative effectiveness of a teacher but are not an absolute indicator of his or her effectiveness.

Value-Added Modeling 101: Using Student Test Scores to Help Measure Teaching Effectiveness

What are student growth percentiles? How can they measure teaching effectiveness?

Student growth percentiles, or SGPs, show how a student’s achievement at one point in time compares with that of other students who performed at the same level of achievement on prior standardized tests. Like VAMs, SGPs are an attempt to estimate the extent to which a teacher (or school) contributes to students’ achievement, but they do not indicate what caused the improvement or decline.

Student Growth Percentiles 101: Using Relative Ranks in Student Test Scores to Help Measure Teaching Effectiveness

Do teachers only affect their own students?

While much of the focus is on measuring and understanding how teachers affect their own students, their effect extends beyond their own students. For example, by affecting the educational achievement of their own students, they also affect the achievement of their students’ future peers and siblings. Discussions surrounding the value of effective teaching should take these broader effects into account.

Teachers' Broad Impact

Are standardized test scores the only student outcome that can be used to measure teachers’ effectiveness?

Although many measures of teachers’ effectiveness rely on standardized tests of academic achievement, teachers influence a broad range of student outcomes, and the magnitude of an individual teacher’s effects often varies across these different outcomes. Examining teachers’ contributions to measures such as student attendance, on-track grade progression, and social and emotional skills can provide a more comprehensive picture than focusing on achievement test scores alone.

Non-Test Effects

How can feedback from students or others be used to understand teachers’ effectiveness?

States and districts often administer surveys to students, school staff, families or others to gauge their perceptions of school or classroom environments. Results from these surveys can provide valuable information about aspects of teaching such as they extent to which they create a supportive learning environment or help students feel safe.

Stakeholder Surveys