Purpose The study aim was to develop and assess the measurement properties of the Functional Impact of Augmentative and Alternative Communication - Educator (FIAAC-E) scale - an educator-reported measure designed to detect change in factors associated with communicative participation in students who use augmentative and alternative communication (AAC). Methods The study had three phases. In phase 1 (content validity), 22 content specialists independently rated the relevancy of 22 dimensions proposed for the new scale. In phase 2 (item generation, face validity), 8 educators independently completed a preliminary version of the FIAAC-E scale and flagged items that were unclear. Next, these educators adjusted the wording of unclear items during consensus-building sessions. In phase 3 (item reduction, reliability, convergent validity), 62 educators completed an online survey that included the revised FIAAC-E scale. Survey data were used to shorten the scale, estimate its reliability, and evaluate support for its convergent validity. Results In phase 1, the 11 dimensions ranked most highly by content specialists were selected for inclusion in the preliminary scale. In phase 2, educators reviewed 113 items and revised 33 to improve clarity. In phase 3, correlational statistics informed the selection of 77 items for the shortened scale. Subsequent data analyses indicated acceptable levels of internal consistency and test-retest reliability and support for convergent validity of the preliminary measure. Conclusion The study provides emerging evidence that supports the FIAAC-E scale as a reliable way to evaluate communicative participation in children and youth who use AAC systems at school.