Many countries have started the process of involving programming in K-12 education. Most experts agree that this will be a positive change, but there are no concrete guidelines on which tools to use, and how to address challenges for the involved teachers. The aim of this study was to describe and analyse teachers' perceptions of integrating programming in technology and mathematics, and their view on programming tools. A case study strategy was used, with two versions of an introductory programming course as the case study units. For both course versions, technology and mathematics teachers taking the course could choose between textual programming in Python and block programming in Scratch. Data have been collected in a mix of submitted essays, programming solutions and researchers’ observations. Findings show that a challenge in learning and integrating programming is the perceived time trouble, while an opportunity is that programming is perceived to be fun. Regarding the choice of tools, the majority of the teachers used Python themselves and mentioned that they could see a greater potential for it as a tool in education. However, many of them stated that they still will start off with Scratch, due to the lower threshold for novice programmers.