The school day has ended but class is not yet over for students heading for their local community centre and a very different sort of classroom -- one built from shipping containers.
The children, who are from China's "floating population" of migrant workers, don't hold Beijing residency, which means they do not have the right to access free education at public schools.
Migrant families who have settled in Beijing are now so permanent that city officials tolerate, but do not certify, about 260 private schools dotted around the capital specifically to serve migrant children. These schools are also often located on marginal land earmarked for other projects, and can be subject to sudden demolition.
This was why Compassion for Migrant Children's Education has decided on the unusual solution of shipping containers for their latest community centre, located in a grimy northeastern Beijing suburb called Heiqiao, where it runs after-school programs for children of migrant workers.
"In the event that we need to move because of urban development, we can just pick up these containers and move with the families," said Yin Chia, the NGO's Australian-Chinese manager.
"These classrooms, they are built out of shipping containers, they are completely renovated."
The charity has already lost one community centre to Beijing's bulldozers as the migrant workers living around it were moved to make way for a shopping centre.
All the programs and classes at the shipping container school are free, making the centre popular. The after school program is limited to 200 students, though anyone can use the basketball court and sports equipment.
The evening is divided into hour-long sessions, with teachers spending the first hour overseeing homework, and sports and arts classes afterwards. The project aims to fill a gap for students who would otherwise spend their evenings home alone while their parents work.
"The homework the teacher gives us to do in the evenings is quite hard," said 9-year-old student Li Jianjing.