Using the context of a 2-wk instructional unit focused on eye and vision health, we developed and validated a multilevel measure of middle school students' interest in science and health careers. This survey contained three subscales positioned differently with respect to curricular content. Interest in Vision Care was most related, but less transferrable to other contexts. Interest in Science was most general, and Interest in Healthcare was positioned between the two. We found that, with two exceptions, items fitted well with validity expectations and were stable across a 2-wk intervention. Further, measures of interest in science, health, and vision-care careers were shown to be reliable and valid. We found that ease of facilitating change across the intervention was generally greater in subscales closely related to the curricular context but that the average magnitude of change in Interest in Healthcare and Interest in Science was not significantly different. We discuss use of these measures in informing instructional efforts and advise that changes in students' perceptions of how science and healthcare relate should be considered in longitudinal analyses.