Detentions and suspensions disproportionately affect children from racial and ethnic minority backgrounds, specifically Black children and children of lower socioeconomic status. These disparities in school discipline are addressed in a cognitive flexibility approach to professional learning through a privately funded district improvement partnership between a team from a university college of education and a local school district. Through facilitated sessions and on-site coaching, educators reflected on their attitudes and assumptions about themselves, their students, and race. Educators worked in teams using protocols for collaborative inquiry, self-reflection, and data-based action planning to transform their disciplinary practices. We highlight the cognitive flexibility approach and the reduction in suspensions of Black students by 54% from the 2014-15 to the 2018-19 school year.