Facing calls for greater emphasis on STEM education in primary school classrooms, teachers may be anxious because of limited exposure to STEM in their own education. The Australian Curriculum: Technologies is new and many teachers are not familiar with its content. Hence both in-service and pre-service teachers (PSTs) require preparation. This research used a case study method to investigate factors influencing PSTs' use of Remote Access Laboratories (RAL) with activities intended to develop their capacity to teach STEM in primary schools. Results highlighted the importance of PSTs' experience of STEM in their own education and showed the benefits of hands-on learning and scaffolding to support preparation of PSTs for teaching STEM subjects.