Merging the content of learning with the motivation of games can be a successful combination, if done properly and supported by the appropriate tool. Towards this goal, we developed Diagramatic an environment used to gamify the in-classroom activity of designing diagrams during a lecture. Using Diagramatic the professor, instead of lecturing about diagrams or showing examples of such diagrams, can design short games where the students could play by competing during the lecture. Diagramatic is a complete environment offering to the professor a design application to create games and a management application. The management application is used for monitoring the games while students play, as well as to present the results to the students after the end of each game, or to evaluate these results after classroom time. The students may use the mobile application on their mobiles to practice by designing diagrams outside of the classroom, as well as to play a game during classroom time, but only after the professor starts this game. The environment handles the communication from students' mobiles to the professor's applications and vice versa, while the students submit their diagrams or receive the correct ones, so to proceed to follow up games. The current version of Diagramatic is tailored for designing flow graphs used for path testing into a higher education software engineering course, but the environment can be used in any similar case requiring the design of diagrams (e.g. math, physics, chemistry).