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Congratulations to the 11th-grade students of Kanti Baden Gymnasium in the canton of Aargau, who “guesstimated” the date of Earth Overshoot Day in their geography class.


Geography teacher Kathleen Noreisch is no newcomer to the concept of the Ecological Footprint. “I first discovered it while teaching at the International School in Bern. It was included in the geography syllabus of the International Baccalaureat Diploma Programme that some 80,000 students around the world take each year,” she explains.

When she left Bern and started teaching at a regular Swiss gymnasium (high-school) between Bern and Zürich, in the Canton of Aargau, she took the Ecological Footprint with her. It’s while prepping for her course that she discovered the Guess-The-Date contest. “The website had not been updated yet for the 2022 contest, but I told my students about it,” she says.

She started with having the students use the Footprint Calculator and discuss their results. “Their reactions always provide a great starting point for a rich conversation where we discuss terms and definitions that are essential to understanding what sustainability means,” she points out. Then she took them on a world tour of national Ecological Footprints, leading to the concept of Earth Overshoot Day… and “guesstimating” its date for 2022.

“I invited them to look at previous year’s dates, observe the trend… and post their individual answers. We discussed the answers, that ranged between July 21st and August 2nd, then we calculated their average: July 27,” Kathleen says.

Last but not least, the course ended with exploring solutions to #MoveTheDate of Earth Overshoot Day, using both Global Footprint Network’s 100 Days of Possibility and the Solar Impulse Foundation’s Efficient Solutions web platforms.

“Guess-The-Date was a fun activity that added to my students’ understanding of the Ecological Footprint vs. resources approach,” Kathleen says. “My students can’t believe it has led to them being recognized as this year’s winners! They’re thrilled!”