Cas was brought onto a team at Rockwell Group to re-imagine the archetypal playground and playground furniture. Working with early childhood specialists and the NYC Parks Department, the large, loose building blocks became a key feature and driving concept of the playground. In an effort to simplify their use and find wider distribution, Cas designed a mobile storage unit to translate the playground into a “pop-up." It can now be found in schools, children's museums, and playgrounds around the world.