Early childhood teachers' social emotional well-being is important for their quality of life, and is associated with their classroom practices, their relationships with children, and with child functioning. This study examines the impact of an intervention; a brief, online course to support teachers' use of stress-management and resiliency practices. Sixty-three, center-based, early childhood teachers completed pre- and post-surveys to assess their knowledge of stress and stress reduction, use of prevention strategies, use of emotion regulation strategies, self-reported stress, and their social and emotional responsiveness to children. Participants also provided feedback about the course design, content, and applicability. Research Findings: After the intervention, teachers demonstrated greater knowledge of stress, stress-reduction and use of prevention strategies, and greater use of reappraisal emotion regulation. Teachers indicated the course was useful, positively affected their work with children, and demonstrated positive changes in their self-reported responsiveness to children. However, after the intervention, they also reported higher levels of personal stress and negative reactions to children's emotions. Practice or Policy: This research provides some evidence that a low-dose intervention delivered online can affect teachers' knowledge and use of resiliency practices. Differences in effects based on teachers' social identities and experiences, and updates to the original course content, are discussed.