On March 31 Netty Oosters successfully defended her Master thesis on group activity plans to improve results oriented teaching. The thesis was done in the Montessori Lyceum Oostpoort (Amsterdam). Working with individual activity plans may be an interesting way to look at personalization of education, but appears to be too time consuming in practice. Therefore, group activity plans are being used to enable differentiation. The questions in this study were: 1. what is the need to work with group activity plans? 2. does working with group activity plans have the desired effect? 3. how can this work method be assured? Two pilot studies were conducted. The format of the group activity plan is tested in two periods. During the first pilot test observations of progress meetings and analyses of group activity plans took place. Based on the insights of the first pilot, the second pilot was conducted to evaluate the effects of this work method on learning results. Teachers have observed each other’s lessons based on the group activity plans. The observations and interviews after the lessons have shown that this working with group activity plans enables teachers to better account for different support needs of the students. The study also shows the importance of learning of teachers in practice for both their own continuing professional development and the quality of the support of the students. Congratulations Netty with this achievement, and thanks Dr Martijn van Schaik for the assessment of the thesis.