This paper focuses on how to use critical reflection in social work education in order to encourage students to critically reflect on their standards regarding assessment, opinions and values about aging. Material, both oral and written, from needs assessments of older persons conducted by 106 social work students was analyzed. The result shows that the students initially interpreted needs based on prejudice and assumptions about aging. However, when using Schön´s three steps of reflection in the exercise, together with knowledge of critical social work theories, students became more concerned and reflected more critically on their assessments. This study shows the possibilities of working with pedagogical exercises in order to increase the awareness and critical knowledge of social work students in order to attempt to reduce discrimination. Educating students in critical social work enables them to learn how to comment on and transform the profession of social work and our unjust society, while questioning their own as well as society’s prejudice regarding the needs of elderly persons.