Adults with their little ones follow a pathway of shells and stones into a warm, serene tent on the stage, where a gentle seaside scene awaits. Through sand shaping, shadow puppetry and inventive sound effects, two performers create tender, magical moments of sea turtles, seagulls, fish, dune grass, ships and sky. As time passes, one of them plays at diving into the water in search of treasure, bringing a poetic undersea adventure to life. Most enjoyed by ages 18 months to 4 years. $15. On stage at the Kennedy Center, March 21 to April 1. kennedy-center.org.