Countdown VR: A Serious Game in Virtual Reality to Develop Mental Computation Skills

Virtual reality (VR) can be utilized to create video games exploring novel ways to control and interact with the environment. VR can be employed to revisit, extend, and enhance old video games to give them a new lease of life. In this article, we describe the game Countdown VR, in which players must use mental computation to reach a target number. Mental computation is used in everyday life, it is used for quick calculations and estimations. Countdown VR is a serious game designed and implemented using the learning mechanics–game mechanics framework. We provide an analysis of different approaches for determining the difficulty level of the game based on a number and target to attain and a selection of numbers combined to reach the target. We assess the user's performance and user's experience in the game, with questionnaires to quantify the related workload, usability, flow, motivation, and potential symptoms of users playing the game. The results provide key information related to the relationships between the subjective and objective evaluations of the proposed VR game by players, with a high correlation between VR sickness questionnaires, and moderate correlations between usability and motivation, flow, and motivation.