Circular Species is toy that combines biodegradable materials and augmented reality to teach kids about the carbon cycle. It comes with three components: a digital app, a physical woolly mammoth toy, and a seed package. When the child is ready, they can bury the toy in their backyard alongside the seeds they plant. Over the course of a few weeks, the external shell of the mammoth biodegrades and acts as fertiliser for the seeds to sprout. The child then goes back to the garden and gets to be a palaeontologist, excavating the mammoth's skeleton that was inside.