Experts say that as play spaces become more sanitised, children are deprived of a chance to connect with nature

Michael Follett is a specialist in children’s play and is passionate about the importance of playing with mud. “It’s so tactile,” he gushes. “You can use it as paint. You can squish it into a pot. You can make a mud pie. You can make cappuccinos!”

As a former play worker and founder and director of Opal (Outdoor Play and Learning), which supports schools to improve play opportunities, Follett is evangelical about the benefits of unstructured outdoor play.