Psychological flexibility (PF), teaching resiliency (tRES), and sense of purpose (SOP) are characteristics that influence physical education teaching sustainability. The study's purpose was to validate an instrument measuring PF, tRES, and SOP relative to teachers' intent to remain teaching (IRT) in high poverty (>60% low-income) schools and evaluate latent variable relationships. A 22-item Teaching Sustainability Questionnaire (TSQ) was completed by 540 teachers working in high poverty schools. Exploratory factor analysis revealed a three-factor structure (PF [[lambda] = 8.6, [alpha] = 0.89], RES [[lambda] = 2.0, [alpha] = 0.87], SOP [[lambda] = 1.4, [alpha] = 0.74]. Confirmatory factor analysis affirmed factor structure, and the data were an acceptable fit for the model ([chi][superscript 2](290) = 681.83, p < 0.001, SRMR = 0.05, RMSEA = 0.05, CFI = 0.94, TLI = 0.93, [chi][superscript 2]/df = 2.35). Convergent/divergent validity values were acceptable (AVE [greater than or equal to] 0.43, CR [greater than or equal to] 0.8), and analysis of the structural model indicated that elevated PF, tRES, and SOP predict IRT. Model re-specification indicated a mediating relationship of PF and tRES with SOP.