Mystery Class is a global game of hide-and-seek. Follow photoperiod clues to search for ten secret sites around the world. Track sunlight to solve a mystery—and discover the reasons for seasons along the way.
* Please note: Due to budget limitations, our spring 2019 Mystery Class challenge will be a replay of a previous year's challenge. We will reveal the locations of the 10 Mystery sites on April 12th but will not be able to hold a year-end contest.