There is no solid evidence supporting many of the positions on teachers and teacher evaluation taken by some school reformers today, according to a new assessment of research on the subject.
The Education Writers Association released a new brief that draws on more than 40 research studies or research syntheses, as well as interviews with scholars who work in this field.
You can read the entire brief (written by Education Week assistant editor Stephen Sawchuk), but here are the bottom-line conclusions of each section:
Q) Are teachers the most important factor affecting student achievement?
A) Research has shown that the variation in student achievement is predominantly a product of individual and family background characteristics. Of the school factors that have been isolated for study, teachers are probably the most important determinants of how students will perform on standardized tests.
Q) Are value-added estimations reliable or stable?
A) Value-added models appear to pick up some differences in teacher quality, but they can be influenced by a number of factors, such as the statistical controls selected. They may also be affected by the characteristics of schools and peers. The impact of unmeasured factors in schools, such as principals and choice of curriculum, is less clear.
Q) What are the differences in achievement between students who have effective or ineffective teachers for several years in a row?
A) Some teachers produce stronger achievement gains among their students than others do. However, estimates of an individual teacher’s effectiveness can vary from year to year, and the impact of an effective teacher seems to decrease with time. The cumulative effect on students’ learning from having a succession of strong teachers is not clear.
Q) Do teacher characteristics such as academic achievement, years of experience, and certification affect student test scores?
A) Teachers improve in effectiveness at least over their first few years on the job. Characteristics such as board certification, and content knowledge in math sometimes are linked with student achievement. Still, these factors don’t explain much of the differences in teacher effectiveness overall.
Q) Does merit pay for teachers produce better student achievement or retain more-effective teachers?
A) In the United States, merit pay exclusively focused on rewarding teachers whose students produce gains has not been shown to improve student achievement, though some international studies show positive effects. Research has been mixed on comprehensive pay models that incorporate other elements, such as professional development. Scholars are still examining whether such programs might work over time by attracting more effective teachers.
Q) Do students in unionized states do better than students in states without unions?
A) Students tend to do well in some heavily unionized states, but it isn’t possible to conclude that it is the presence or absence of unions that cause that achievement.