Audrey Amrein Beardsley writes here about Houston’s experience with value-added evaluation of its teachers.

The Houston Independent School District (HISD) contracted with William Sanders’ SAS to provide a model to calculate the “value-added” of its teachers from 2007-2017.

Teachers objected that the method of calculating their scores was opaque. They couldn’t learn how to improve their practice because Sanders’ methodology was proprietary and secret.

Teachers were fired based on their VAM scores.

The Houston Federation of Teachers sued to stop the use of the “black box” method.

In 2017, a judge agreed and enjoined the use of VAM.

Thus by now, after a decade of VAMMING teachers, Houston should have identified and removed all the “bad” teachers and employ only “effective” or “highly effective” teachers.

But the state threatened to take over the entire district because one high school–Wheatley– has low test scores. Wheatley High School has a disproportionately large share of students who are poor and have special needs, has low scores, even though all of its teachers–like all of Houston’s teachers–were VAMMED for a decade.

If VAM were effective, HISD should be the best urban district in the nation.

All achievement gaps should have closed by now.

Why is the state–which has no expertise in running a large urban district–taking control away from the elected board?