Early childhood teachers play a critical role in the kindergarten readiness of preschool age children. Yet, they often receive little and insufficient training in the use of evidence-based practices that can increase academic success and prevent undesired behaviors. As a result, preschool teachers tend to use more exclusionary practices when disciplining students. A promising strategy for developing the skills of preschool teachers is the use of bug-in-ear coaching, a coaching strategy where a trained individual provides in-the-moment support to a teacher from a location outside of the classroom. This study examined bug-in-ear coaching to support preschool teachers in using opportunities to respond during explicit math instruction. A multiple baseline design across teachers was used to assess the impact of the intervention on the teachers' rates of implementation of opportunities to respond. Bug-in-ear coaching was associated with an increased rate of opportunities to respond for all teachers during the intervention with a functional relation for two out of four teachers. All teachers' rates of opportunities to respond were below their intervention rates during maintenance. Further, teachers reported enjoying the intervention and the opportunity given to improve their practices. Teachers also expressed their desire to have this level of coaching in their centers.