THE bell indicating school’s out was not ringing yet, but 30 sixth-graders of the Kelapa Island State Elementary School (SD) 02 in the Thousand Islands were already pouring out toward the beach about 100 meters from their classrooms. Ten of them took off their school uniforms and started wading into the sea. Cries of joy were heard amid the roaring Java Sea waves.

They picked up a series of pipes in the form of a table from the bottom of the s