Spring 2020*

*Please note: Our spring 2020 Mystery Class challenge is a replay of a previous year's challenge. You have open access to all of the season’s clues (Weeks 1-11). We will reveal the locations of the 10 Mystery sites on April 13, 2020.

Week 2
February 3

It's the second week of photoperiod clues. What do they reveal about the locations of mystery sites?

Week 3
February 10

With three weeks of photoperiod clues, which sites are north and south of your hometown?

Week 4
February 17

This week, explore time zones to get ready for special time clues coming in March.

Week 5
February 24

It's time to zero in on the line that divides the globe into Eastern and Western Hemispheres.

Week 6
March 2

The Vernal Equinox is coming! Explore this to be ready for next week's Time Clues.

Week 7
March 9

The Time Clues are here! Using equinox sunrise times, estimate and then celebrate longitude.

Week 8
March 16

It's time for the first set of Continent, Country, and City clues. Week by week, these clues reveal fun facts that will help progressively narrow your search.

Week 9
March 23

The second set of Continent, Country, City clues is here. Build upon last week's and narrow your search even further.

Week 10
March 30

More clues are flying in!
The third set of Continent, Country, and City clues is here to narrow the search. Final clues are next week.

Week 11
April 6

It's time to fetch the final clues
to help you discover the secret locations and submit your answers.