It is widely accepted that problem solving and reasoning during small-group work with either peers only or with intervening teachers may contribute to children’s language and cognitive development, depending on the participants’ discourse. Most research is experimental of nature, focusing on teacher-initiated problems. Therefore, in this thesis young children’s construction of their own problems during small-group work in early childhood education is investigated, through a detailed analysis of videotaped and transcribed problem-solving interactions.The most important findings are: (1) Whether the teacher is present partly determines young children’s discourse. In teacher’s absence children produce significantly longer and more complex turn...