The aim of this study is to investigate how mathematics teachers use formative assessment to make the course objectives clear to the student. This is part of a wider aim in Sweden to find ways for improving mathematics teaching. Qualitative semi-structrured interviews and observations were used for collecting data. Different approaches to integrate formative assessment in their classrooms is discussed: questioning, discussions in whole-class, group work and assessment and feedback. The analysis of the results indicated that the teachers thought differently about how to integrate the course objectives in their planning. Two out of three teachers did not consciously base their planning on these which could be due to a lack of time to discuss the curriculum amongst the teachers. Conditions that make implementation of these approaches more or less easy include the teacher’s view of formative assessment, the school-based support and the impact of high-stake tests such as national tests.