Swing Time is an interactive playscape composed of 20 illuminated ring-shaped swings. The installation activates a temporary park between the Boston Convention and Exhibition Center and D Street to create a new type of city park. Custom fabricated from welded polypropylene, the swings are designed in three different sizes so that the community can engage, exercise, and play with Swing Time as individuals or in groups. LED lighting within the swing is controlled by a custom micro-controller, signaling the swing's activity level. An internal accelerometer measures the acceleration forces of the swing. When forces are static and the swings are not in use, they emit a soft, white light that illuminates the area. When the swings are in motion, the micro-controller switches the light from white to purple, creating a more colorful glowing effect. Swing Time's responsive play elements invite users to interact with the swings and with each other, activating the urban park and creating a community laboratory of the Innovation District and South Boston neighborhoods.