In this study, I examined how children understand the activities teachers at a preschool offering in sustainable development. The study was conducted in a kindergarten with profiling green flag. I have used a qualitative research method and through this come to the conclusion that shows that children who studied at this nursery in particular, may explain the standards that relate to sustainable development. To some extent, they also describe facts. They find it difficult to explain the causes and connections. This result is also given recommendations on how further work on sustainable development can be conducted in preschool.