My post today at WHYY’s Newsworks examines new research out from the Gates Foundation on the validity and fairness of using student standardized test scores to evaluate teachers.

One of the most contentious issues surrounding education reform is whether or not one can measure teacher effectiveness through student test scores. While other professions have long used objective data to measure performance– doctors get rated on patient outcomes, lawyers get rated on successful resolutions – rating teachers is considered far more complex and politically wrought. Historically, schools have relied on subjective observations, usually performed by principals or supervisors.

Teacher unions have fought to preserve this system on the grounds that using test data as a measure of effectiveness penalizes those who work with kids with disabilities, or those from impoverished homes, or those just learning English.

Now, a new study offers evidence that objective data can fairly evaluate teachers in spite of those differences.

Read the rest here.