Purpose: The purpose of this paper is to present how experiences gained from a theory-informed lesson study -- learning study (LrS) -- in regard to a specific learning goal can be shared and used by other teachers in new contexts. Design/methodology/approach: A group of teachers worked together in a cyclic, iterative process of planning, evaluating and revising teaching. The aim was to provide possibilities for grade 2 and 3 students to become familiar with negative numbers. The teacher group came to the conclusion that the students needed to be able to differentiate some aspects of negative numbers. The conjecture was put to the test in a follow-up study (FS) with five new teachers and eight classes. One lesson was taught based on the empirical findings in the LrS. Findings: The results suggest that teachers' collaborative work has possibilities to produce knowledge about critical aspects of learning that can be communicated and adopted in new contexts. The teachers in the FS were able to make sense of the results from LrS and incorporate the critical aspects in their teaching in a way that enhanced students' learning. Originality/value: It is demonstrated that teacher collaboration in LrS can create knowledge that goes beyond the border of the local context.