Teaching situations designed by experienced teachers to foster students' mathematical flexibility

A community of inquiry consisting of seven high-school teachers chose a challenging long-term goal of designing teaching situations to foster students' mathematical flexibility across the curriculum. In this context, we explored the teachers' design products. Based on the data from the teachers' portfolios and recordings of the community meetings during a year, we identified three types of situations that the teachers designed: multiple-solution situations, "find a better strategy" situations, and dead-end situations. We argue that our findings can inform the future design motivated by challenging didactical goals and that the community of inquiry is an appropriate setting for the development of mathematics teachers' task knowledge and design skills.