Knee Deep invites children to jump in and explore unexpected worlds of different proportions with their feet. Children stomp through a loose narrative that plays with scale, point of view, and cause and effect to gain perspective about how their actions relate to the natural systems of our world. The installation combines real-time green screening, computer vision and stomp detection. We created this project for the 2009 Cinekid Festival in Amsterdam with funding from the Amsterdams Fonds voor de Kunst (Amsterdam Fund for the Arts).