In evaluating curriculum qualitative research methods such as interviews and observations are very important. Our institution has evaluated some aspects of the National curriculum reform. One of these aspects was the process that took place in the classrooms. We were interested especially in how problem approach in teaching and how active role of pupils are realised. The paper will present the theoretical background for observations, the observation check list and some of the most interesting results from the study. The main focus will be on the connection between our evaluation needs, theoretical background and observation checklist as the key instrument.