Early care and education (ECE) settings are influential in shaping children’s early experiences. Informed by the Job Demands-Resources model, this study had two aims. First, we examined how ECE teachers’ physical (i.e. muscular skeletal strain and infectious disease experience) and psychological (i.e. depression and job dissatisfaction) job strain was associated with the quality of their interactions with children. Second, we tested whether job resources, including supervisor and co-worker support, buffered these associations. We examined survey responses from 44 toddler teachers working in centre-based classrooms with children aged 15–36 months and assessed the quality of the classroom using the Classroom Assessment Scoring System – Toddler (CLASS-T; La Paro et al. 2012. Classroom Assessment Scoring System (CLASS) Manual, Toddler. Baltimore, MD: Paul H. Brookes). Results indicated that teachers experienced a range of physical and psychological job strain. Co-worker and supervisor support were not significant moderators of the ECE teachers’ job strain- classroom quality association. However, contrary to the mechanisms theorised within the Job Demands-Resources model, a main effect of co-worker and supervisor support on classroom quality, such that higher levels of perceived social support was related to higher classroom quality. Due to the significance of classroom quality for young children, understanding ways to create a work environment of rich social support stands to benefit teachers and the toddlers in their care. (author abstract)