Out of identified general didactic problems when teaching evolutionary theory, structured learning situations for pre-service teacher students were created together with performance assessment. The students’ discussions showed almost no use of evolutionary concepts and well-structured learning situations failed as many students worked in an arbitrarily manner. The performance assessment showed anyhow good results as questions with open answers gave opportunity for constructive thinking. One conclusion is the strength in open questions, promoting the students’ creation of reasonable explanations within a theoretical framework.