This study examined the intended and unintended consequences associated with the Education Value-Added Assessment System (EVAAS) as perceived and experienced by teachers in the Houston Independent School District (HISD). To evaluate teacher effectiveness, HISD is using EVAAS for high-stakes consequences more than any other district or state in the country. A large-scale electronic survey was used to investigate the model's reliability and validity; to determine whether teachers used the EVAAS data in formative ways as intended; to gather teachers' opinions on EVAAS's claimed benefits and statements; and to understand the unintended consequences that occurred as a result of EVAAS use in HISD. Mixed methods data collection and analyses were used to present the findings in user-friendly ways, particularly when using the words and experiences of the teachers themselves. Results revealed that the reliability of the EVAAS model produced split and inconsistent results among teacher participants, and teachers indicated that students biased the EVAAS results. The majority of teachers did not report similar EVAAS and principal observation scores, reducing the criterion-related validity of both measures of teacher quality. Teachers revealed discrepancies in the distribution of EVAAS reports, the awareness of trainings offered, and among principals' understanding of EVAAS across the district. This resulted in an underwhelming number of teachers who reportedly used EVAAS data for formative purposes. Teachers disagreed with EVAAS marketing claims, implying the majority did not believe EVAAS worked as intended and promoted. Additionally, many unintended consequences associated with the high-stakes use of EVAAS emerged through teachers' responses, which revealed among others that teachers felt heightened pressure and competition, which reduced morale and collaboration, and encouraged cheating or teaching to the test in attempt to raise EVAAS scores. This study is one of the first to investigate how the EVAAS model works in practice and provides a glimpse of whether value-added models might produce desired outcomes and encourage best teacher practices. This is information of which policymakers, researchers, and districts should be aware and consider when implementing the EVAAS, or any value-added model for teacher evaluation, as many of the reported issues are not specific to the EVAAS model.