Thirdly, players felt that games are effective because they involve learning by doing. For example, David thought that gaming can enhance understanding. '... calculation of parameters etc. is normally hard. When the equations are on the paper, one usually just tries to absorb them by rote learning, mainly. But in the game equations appeal in practice and one can clearly see where they come from'. On the other hand one team stressed that learning by doing is effective, because one is so involved with the experience and can affect on the system. 'When one do things in the game, one is so involved in doing ... we really were ... gaming is so much more interactive than lectures that include only one channel ... in the game you can see cause and consequence chains more clearly'. Previous statements reveal why computer games can be effective and captivated. However, the development of such games that help players to understand cause and consequence chains is really hard. One big question is, what kind of game elements can be used to facilitate reflective thinking?