For those of us in the Northern Hemisphere, fall is upon us. The leaves are already changing colors here in Chicago, a constant reminder that winter is coming. These special paper leaves are designed to work as thermometers, providing a vague sense of the weather by changing colors.
Inspired by actual leaves, designer Hideyuki Kumagai created these paper leaves which are embedded with a chemical that changes color based on temperature. When the leaf turns brown, it’s cool out, when it’s green, it’s temperate, and when it’s yellow, it’s hot.
These leaves come in packs of either 5 larger or 8 small and sell for $22(USD) over at Re!Ex!!Japan!!!. If you happen to live in Japan, I’m sure you can get them for less – or you could just install a weather app on your phone and watch the actual leaves change colors.