Serious games can be used as learning tools since learning games are more in correspondence with the current generation of students, foster students' motivation, and increase the learning effects, making learning meaningful to students. This paper presents a conceptual model for representing designs coming down to a puzzle-based game implementing an active learning method that describes the activities flow for learners. Each activity refers to a collection of puzzle pieces needed to perform the activity. In order to support the performance of individual activities, micro-scaffolding support, such as question or hints, can be also defined using our proposed model.