Open Rain is a public welfare organization at Diligentia College. The name of the organization is derived from the phrase "After the storm comes the rainbow," with the hope that everyone involved in charitable activities, as well as those helped by these activities, can push through the storm, find the rainbow, and see hope.

Open Rain guides students to actively serve society, help vulnerable groups, protect the ecological environment, and enhance their sense of social responsibility and team awareness. It aims to increase their understanding of charity and establish correct views on life, values, and the world.

Since its establishment, Open Rain has organized various charitable activities such as beach cleaning at Shenzhen Bay, bird watching and bird protection, mangrove protection, and summer teaching support. With its creative and exciting charitable activities and widespread charitable influence, it has received unanimous praise both inside and outside the school. It was awarded the 2022-2023 Innovation and Creativity Student Organization Award by The Chinese University of Hong Kong (Shenzhen).