Children's stress in day care is related to the stressful qualities of the environment and to children's orientations in that environment. The study involved 55 children in five day centres in Finland. Baseline saliva samples for measuring cortisol (stress) levels were collected five times during the day. Children were interviewed to measure their orientation in regard to perceived change. The educators of the groups evaluated the learning environment qualities. The high cortisol levels at the wake-up time were correlated with chaotic, hectic and emotionally restricted learning environment qualities. However, in the afternoon, the correlations between cortisol levels and the learning environment had disappeared and were replaced by children's orientation to change. Children with more accommodative views had lower cortisol levels and children with uncertain views had higher cortisol levels. The children's different orientations seem to impact their stress levels and participate in the production of the learning environment stressful qualities. (Contains 7 figures and 3 tables.)