Du Du and his friends go to a kindergarten run by the military region. The students at the school are children from the compound, and the teachers are professionals, making it a high-standard institution.
The five kids all attend the same school, although not the same class. Du Du, Mao Dou, and Huahua are in the junior class; little leopard is in the middle class, and Haiyang is in the senior class. Their classrooms are next to each other, just a few steps apart, which is why Du Du and Mao Dou sometimes can't sit still and often go to visit their older brother's classroom.
The teachers are aware of Du Du and his friends' backgrounds and are quite lenient with the three little ones, letting them play as long as they don't cause trouble.
Although Du Du and his friends have overbearing personalities, under Mr. Yun's guidance, they never initiate trouble; they prefer to scheme behind people's backs rather than attack someone face-to-face.
