Successfully carrying out a secondary school physics inquiry requires a considerable amount of procedural and content knowledge. It further requires knowledge of how and why maintaining scientific standards produces the best available answer to the given research question. To this purpose, a series of five inquiry activities was developed and tested in a single case study with students aged 14. The test shows that students indeed come to use a more scientific approach to inquiry tasks and understand why they should do so. We believe that this series of activities can serve as a starting point for more complex physics inquiries.