We held an event called balloon release at school. A balloon release is an event in which balloons filled with gas are released at the same time so that they float in the air. It was held at my school to commemorate the founding.
The children and adults of the whole school released the balloons all at once from the school yard, and the balloons disappeared into the sky. (By the way, I was told that the balloons released into the sky are made of materials that return to nature, not garbage. SDGs are also becoming important…) Hundreds of balloons go up all at once. It was amazing and inspiring to see the senary.