Following the recommendations of a 2013 instructional audit, the Academically or Intellectually Gifted department implemented a co-teaching instructional strategy in 41 volunteer schools starting in the 2014-15 school year. Implementation data and discussions with central office staff suggest that while implementation fidelity was relatively strong in the first year, it declined in 2015-16. Still, the first year of implementation offered evidence to guide any future co-teaching implementation. First, the "one teach, one assist" method of co-teaching was most frequently observed, suggesting that co-teachers may have defaulted to one of the less optimal instructional strategies under the model. Second, AIG teachers and co-teachers perceived the initiative similarly but differed on a few particularly meaningful survey items pertaining to the perceptions and role of the specialist. Third, AIG students and non-AIG students in co-taught classrooms were similarly engaged. Finally, students in co-taught classrooms significantly outperformed their non-co-taught peers in science, but not in math or reading.