The COVID-19 educational crisis has generated both psychosocial risks and growth opportunities for teaching staff; these are challenges to be addressed from the perspective of sustainable development in SDG 3 Health and Well-being and SDG 4 Quality Education. During the pandemic, a character education training experience was carried out for principals and teacher coordinators, with the dual purpose of developing professional competencies for the application of positive psychology in educational centers and strengthening teacher well-being: specifically, dedication and enthusiasm in conjunction with personal resources such as self-efficacy and resilience. The multicomponent intervention based on positive psychology applied to education was carried out with a sample of 32 teaching coordinators and school principals (mean age 45.9 years; 93.75% female staff and 71.8% between 16 and 21 years of experience) from different departments in Uruguay. The results suggest that the intervention was effective, detecting higher scores in the post-test in self-efficacy (F = 18.17, p < 0.001, η2 = 0.40), resilience (F = 13.41, p = 0.001, η2 = 0.33), dedication and enthusiasm (F = 8.09, p = 0.008, η2 = 0.23), and teacher training (F = 8.36, p = 0.007, η2 = 0.24). It is concluded that the training program can provide an opportunity for improving teacher health and well-being, as well funcitoning as a device for promoting teacher professional development.