In the midst of Covid-19, playgrounds are closed. However, one day they will reopen. Yet when will social distancing end and when will we pick up our trust again? What kind of information would the public need to go back to the playground? This urban sensing project focuses on detecting public movements using a Human Presence Sensor. At the playground level, the project’s audience are children. Playful LED displays will stay engaged and interactive with kids, presenting a sense of wondering. At the city level, information collected by the sensor will be aggregated and used for parents who need to know whether a playground is busy. The information would also be helpful to Department of Park and Recreation, who manages these parks. Playground Pulse, a name and a project inspired by Rafael Lozano-Hemmer’s Pulse Room, translates analog to digital and facilitates the public activities on children’s playgrounds.