Serious games are generally considered a good alternative to improve motivation to learn. A game should have meaningful mechanics and elements to involve the players and to keep their attention. Each person has his own motivation to play games. This leads to different types of players and consequently to the need of different types of elements to keep them engaged. Understanding the player's behaviour is an important issue to improve support in the game. While the designer of a serious game focus mainly on its educational value, it is also important to incorporate fun elements in the game. We are developing a serious game aimed to help the development of basic computer programming skills. Our challenge is to create a game that provides effective self-learning support while keeping the student engaged in the game's missions. This paper deals with the game features and their evaluation. The game has missions covering basic concepts of computer programming: sequence of actions, variable manipulation and conditionals. In this research, we are concerned with evaluating the game enjoyment. We conducted two experiments with groups of students from completely distinct knowledge areas. First, we applied the game in a Portuguese Education Sciences class that included essentially female students. Next, we performed a play test in a Brazilian first semester of Software Engineering undergraduate class composed essentially by male students. We believed that we would identify a larger set of needs if we diversified the types of players that tried the game. Consequently, if the game satisfies their needs, we would reduce the possibility of failure of the game. The EGameFlow instrument was used to measure the enjoyment. Findings show that the game entertains the players even if the programming tasks are hard. However, some improvements are necessary to foster self-learning. Finally, the paper presents future work that aims to include new challenges and missions in the game and to improve the enjoyment.