Background: This paper builds on the growing focus on learning about teaching science with digital technologies, and the relationship between different elements that constitute teacher knowledge and how these are captured and understood during teacher education program. Purpose: The aim of the paper is to capture and understand how student teachers integrate digital technologies into their science teaching. In the paper, research on Pedagogical Content Knowledge (PCK) is used to inform the discussion of Technological Pedagogical Content Knowledge (TPACK) the integration of technology into the teaching of a particular science content. Content Representation (CoRe) as a reflective tool is modified to a Technological Content Representation (T-CoRe) to stimulate 24 primary student teachers´ reflections on how to integrate digital technologies into science teaching. Design and methods: After completing the T-CoRes, the student teachers participated in group discussions that aimed to stimulate a deeper reflection on how and why they integrate digital technologies into their science teaching. The data consist of student teachers´ completed T-CoRes (n = 12) and audio recorded group discussions (n = 6) to provide examples where the student teachers reflected on knowledge components of TPACK, both separately and integrated. A qualitative content analysis was performed to identify examples of participants' understanding of how to use digital tools when teaching a specific science topic. Results: The results demonstrate that the T-CoRe helped student teachers to reflect on their teaching of science with the use of digital technologies and made explicit the ways in which technology, content and purpose are closely linked in teaching. Conclusion: The practices and processes highlighted in this paper will help to inform the involvement of student teachers in capturing and developing a knowledge base for using digital technologies in their science teaching.