In mathematics education, student collaboration is often emphasised as desirable. The focus of this paper is on students’ positioning during collaborative problem solving and problem posing on the mathematical content combinatorics. The study utilises the Learning Design Sequence model for lesson design and positioning theory as an analytical framework. In a sequence of lessons, students worked with both problem solving and problem posing, using different ways of representing their solutions, such as pictures, physical objects, and digital animations. Two cases of collaboration between 6-year-old students are used to illustrate their positioning during this sequence of lessons. One conclusion is that, when collaborating, students’ experiences of each other as learners in general and mathematics learners in particular have influence on their positioning which in turn may influence their possibilities of meaning making in mathematics.