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EdTech Assessment Toolkit

Teacher Evaluation (Houston, US)

Value-added model

The Houston Independent School District (HISD) in Texas introduced a value-added model (VAM) system named the Houston Independent School District Educator Performance Assessment (HISD EPA) to evaluate teachers’ performance. The HISD EPA utilised a statistical approach to assess teacher effectiveness by analysing student achievement data. The HISD EPA employs a sophisticated statistical methodology to calculate value-added scores, which aim to measure the impact individual teachers have on their students’ academic growth over time (Amrein-Beardsley & Collins, 2012).

In 2014, a group of teachers, in conjunction with the Houston Federation of Teachers (HFT), lodged a lawsuit against the HISD, contesting the use of value-added scores in their evaluations. The teachers contended that the system was flawed, unreliable, and resulted in unjust evaluations based on elements beyond their influence, such as student demographics and external factors (Strauss, 2014). In April 2017, a judge decreed that the use of the HISD’s teacher evaluation system was unconstitutional. The court determined that the system infringed upon teachers’ due process rights, as it failed to offer them a meaningful chance to contest their evaluations. The ruling further implied that the system lacked adequate transparency and did not sufficiently account for individual teacher performance (AFT, 2017).

Snapshot (July 2023)

System task/function: Teacher Evaluation
Model: Value-added Model
Deployment: Algorithmic teacher evaluation
Location of application: Houston (US)
Rationale for introduction: To automate the ongoing evaluation of teachers
Vendor: Houston Independent School District
Pricing: N/A
Data and computation: Teacher data matched with student performance data
Inequalities/harms: Unjust evaluation procedure
Status: Removed
Authority/regulation: District level
Unintended consequences: reliability, bias, teacher attribution, and validity (see Amrein-Beardsley & Collins, 2012), encourages teachers to work in higher achieving schools
Sanction/redress: 237,000$ US, the district agreed to no longer use the software

References/further reading

AFT. (2017). Federal Suit Settlement: End of Value-Added Measures for Teacher Termination in Houston. Retrieved from

Amrein-Beardsley, A., & Collins, C. (2012). The SAS education value-added assessment system (SAS® EVAAS®) in the Houston Independent School District (HISD): Intended and unintended consequences. Education Policy Analysis Archives. 20, 1-28.

Strauss, V. (2014). Houston teachers sue over controversial teacher evaluation method. Retrieved from