From Tennessee Education Report on the subject of TVAAS data:
Well, it could mean that Tennessee’s 6th and 7th grade ELA teachers are the worst in the state. Or, it could mean that math teachers in Tennessee are better teachers than ELA teachers. Or, it could mean that 8th grade ELA teachers are rock stars.
Alternatively, one might suspect that the results of Holloway-Libell’s analysis suggest both grade level and subject matter bias in TVAAS.
In short, TVAAS is an unreliable predictor of teacher performance. Or, teaching 6th and 7th grade students reading is really hard.
Read more about bias in TVAAS scores by grade level and subject
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