Did the Gymnasium boost students ability? There are different opinions about this. Some argue that this is the cases and even after testing performance in grade four, those who were admitted to a Gymnasium outperformed their peers who were not at grade six. That was also the interpretation of Prof. Dr. Dr. Lehman, who did the study. He stated: "The findings indicate that the Gymnasium help students of all social classes reach their full mathematical potential". Others however, who have reanalyzed the data, claimed that those attending a Gymnasium were different ab initio and could not properly be compared to those attending a primary school. The data is of high political relevance as those who are in favour of the tripartite system and those who are in favour of comprehensive schools both use it to prove their point. Those, who are in favour of comprehensive schools, claim that the data shows that the primary schools which resembles a comprehensive schools boost children's ability, while those in favour of the tripartite system argue that the data shows the Gymnasium boost students ability.