However, these evaluations did not find evidence that Tech Prep improved students' scores on standardized academic achievement tests, and findings were mixed on whether Tech Prep improved students' postsecondary achievement or labor market outcomes. The last national evaluation of Tech Prep programs, conducted in 1997, found that Tech Prep programs were not always implemented as envisioned in the legislation, perhaps lessening their impact on student outcomes.
However, these studies failed to uncover any evidence that Tech Prep had a positive effect on students' academic performance, and findings were split regarding whether Tech Prep improved students' post-secondary education or job market prospects. The final nationwide evaluation of Tech Prep programs, conducted in 1997, discovered that the actual implementation of Tech Prep programs often diverged from their intended objectives as outlined in the legislation, which may have reduced their impact on student outcomes.