This study focuses on a recording from a week of third-grade classroom sessions. The recording was used to train new teachers in a certification program and provided data for a learning community that was studying classroom discourse. The third-grade teacher was described as being "outstanding" and "culturally responsive" by the university professor who had been using the recording to train teacher candidates. The teacher was indeed innovative in supporting cultural diversity and was responsive to all students throughout the week, except during a particular literacy lesson, the subject of this study. Critical discourse analysis revealed prioritizing White males, disrespecting a Mexican-American boy and neglecting females. The recording was later withdrawn from the certification program because it did not reflect exemplary teaching, yet its initial use points to an urgent educational problem: even experienced teachers exhibit microaggressions toward students of color and female students, and experts in teacher education do not readily recognize them when they occur. Microaggressions can appear subtle and inconsequential, yet they have a negative impact on the teacher-student relationship.