The purpose was to study children`s thoughts and experiences on photosynthesis, used qualitative interviews with semi- structured questions. The study included eight children, four and five year olds. The children drew a picture of a plant and shared their thoughts and experinces regarding plant growth, nutrient and energy uptake. In a playful and entertaining way, I conducted a learning play and an experiment with the purpose of clarifying the photosynthetic process. Thereafter the children were interviewed again to see if the children gained a deeper understandning of the photosynthesis among the children. Based on the result the responses from the first interview of most of the children. At the second interview more children understood the significant role of the sun for the photosynthetic process as well as the plant needs roots for survival and growth.