Critics encourage the process of "reflection" as a prerequisite for professionalizing how teachers behave in the classroom. Reflection helps in recognizing areas in need of improvement. Self-reflection is hence one of the teacher's most important skills in order to work constantly on one's teaching and how to improve it. However, the practice of this process is most often restricted to a short, oral evaluation of certain lessons with a supervisor or colleagues and never fully learned by most teachers. Consequently, in 2009, Dr. Claas Wegner initiated the Bielefeld University (Germany) Reflection-Wiki. In the course of the project "Kolumbus-Kids," University students teach weekly double-period sessions to children from regional schools. Their teaching behavior and personality are evaluated with the help of this Reflection- Wiki. The online tool assists student teachers in developing self-reflection skills through offering them a structure that transforms reflection into an organized, understandable process.