Children and youth who are deafblind with multiple disabilities have several identified risk factors for experiencing toxic levels of stress, and such stress is known to impair physical, mental, and emotional health. This single-case multiple baseline study examined the frequency and duration of behaviors thought to indicate stress, the duration of active participation in class activities, and the effect of the stress hormone salivary cortisol to determine the extent to which participating students with deafblindness were experiencing stress and how it affected their behavior and participation in school activities. Examined were three groups of intervention strategies designed to decrease stress and its behavioral manifestations and, at the same time, increase active participation. The selected intervention strategies did significantly lower behaviors that had been thought to indicate stress and concomitantly increased active participation. However, sampled salivary cortisol demonstrated only one instance of actual toxic stress. This finding is discussed from the perspective of delineated protective factors against toxic stress.