This online math game allows you to review the operations on hours, minutes and seconds. It is an excellent training exercise for the calculation of durations. Combined with the lesson reminders on hourly calculations, it allows you to review and master the rules of sexagesimal calculation. The game is presented as a multiple-choice questionnaire (MCQ), to win you just have to find the right answer in a list. In case of error, the game proposes the right answer and a link that relies on the calculation engine of the site to give the steps of calculation.