Can participation in a 4-day workshop change science teachers' beliefs about reformed science teaching? We observe a significant difference between pre- and post-workshop surveys and explore an unexpected relationship involving teaching experience. Results of this exploratory study indicate a significant correlation between high school science teachers' years of teaching experience and positive changes in beliefs about reformed teaching practices. Novice teachers hold more reformed beliefs pre-institute, but post-institute surveys revealed the two groups, experienced and novice, are statistically indistinguishable. We use our observations of the statistically significant changes in biology teachers' responses on the Beliefs About Reformed Science Teaching and Learning instrument (BARSTL) to support our claim that a 4-day Advanced Placement Summer Institute (APSI) in Biology can advance teachers' beliefs toward more reformed teaching. Furthermore, these findings provided evidence for us to suggest that veteran teachers are more malleable in their beliefs about reformed science teaching than one might expect (AP®, "Advanced Placement®, and AP Biology® are trademarks registered by the College Board, which is not affiliated with, and does not endorse, this article").