At Toun Fa, every classroom is packed. Students sit in rows dutifully reciting their Mandarin lessons, scrawling Chinese characters into their notebooks. Demand has been so high at Cambodia’s oldest Chinese-language school, principal Doung Sitha says, that there is barely any more room to expand.

“More people wanted to learn Chinese since our ties became closer with China and there has been more business, factories – so the need is big,” he said. “We originally said that the maximum number of students in a classroom would be 40-45, but now it’s more than 50.”

Since it was founded in 1914, Toun Fa has catered to Cambodians of Chinese descent, especially the large community of Teochew people from Guangdong province, but these days the student body is diversifying. Alongside students with Chinese heritage are more and more Khmer students looking to get a leg up on their peers as Chinese investment – and the opportunities for locals that come with it – pours in.

With 8,000 pupils, Toun Fa is the largest Chinese-language school in Southeast Asia, and one of 55 in the country, according to the Cambodian-Chinese Association.

Its growth mirrors the spread of Mandarin throughout Cambodia, with efforts to expand language education rapidly picking up steam, in large part funded by the Chinese government. Through the local branch of the Confucius Institute (CI), whose network of language schools is in more than 140 countries, China is expanding its reach in the Kingdom and finding the Cambodian government more than happy to accept its services.

The local CI works in collaboration with the Royal Academy of Cambodia. At night and in the early morning, students come to the Institute for language classes, but much of the work CI conducts takes place elsewhere, including within government ministries.

Eight years since Cambodia’s CI was founded, it now has 80 teachers in the country sent by Hanban, the language promotion wing of the Chinese government. Sixty of them are volunteers. The Institute also has 27 “teaching classrooms” in the country, where Mandarin is taught by Hanban teachers – at high schools, private companies, in government ministries and elsewhere.

And in July, a “Mandarin Center” was inaugurated at the Ministry of Defence’s headquarters in Phnom Penh to teach officials and soldiers in the Royal Cambodian Armed Forces. Bradley Murg, a professor at the University of Washington and Seattle Pacific University, and an expert on China-Cambodia relations, sees the opening at the Defence Ministry as a “highly significant signal”. He points to two reasons: it coincided with the discontinuation of military exercises between the United States and Cambodia, and the first batch of students consists of upper-level officials.

“That is a pretty strong signal of where your future intentions are as regards military cooperation,” he said.

Sok Touch, the head of the Royal Academy, explained that the Academy offers courses in many languages, not just in Mandarin, but that the military “is a special case” in its needs.

“Most weapons and equipment [in the Cambodian army] are imported from China, and the instructions to use them are in Chinese, and there are different terminologies for different [military] divisions,” he said, explaining that a soldier from the parachute unit would need to understand specific terminology related to his area of focus. “Military officers also need to learn Chinese in order to communicate with Chinese military officials within their work. They need to translate military documents from China,” he added.

Requests for Chinese training have also come from at least seven other ministries, with the Ministry of Commerce in the process of setting up a “teaching classroom”, and the Phnom Penh police department also planning classes.

The flood of Chinese tourists, alongside investment, has created challenges for local officials, said Xiulong Xia, the Chinese director at Cambodia’s Confucius Institute. “Many many Chinese come here, they pick up the [police] hotline and they can’t understand Chinese,” he said.

“That’s the problem. So the first batch will be those working the hotline.”

On top of providing courses free of charge for government officials, CI focuses on expanding Mandarin proficiency among the general public. It works to train local Chinese teachers, has helped to set up classrooms in provincial areas of the country, and also selects 50 Cambodian students each year to study abroad in China.

The effort is part of the Chinese government’s global attempt to expand its soft power by exporting its language. China specialist and George Washington University professor David Shambaugh has estimated previously that the Chinese government invests $10 billion each year on its soft power efforts.

As Xia points out, language institutes are not just a Chinese phenomenon, with most Western powers providing government-sponsored language classes abroad. But the scale of China’s investment in its language expansion is incomparable, and has come with controversy. In the United States especially, Confucius Institutes have been criticised as propaganda arms of the Chinese.

But Xia insists that Cambodia’s CI serves as a bridge enabling greater understanding between two cultures that are interacting more and more. Students are taught about Chinese culture and habits, while the teachers are steeped in local norms.

“We have to know Cambodia. Cambodia also has to know China. Then you have a friendship. That’s the value for this” for the Chinese government, he said. “Because many conflicts – even war – are caused by misunderstanding, and lack of communication.”

Regardless of controversies elsewhere, in Cambodia the demand for Chinese education is largely about opportunities, with students at Toun Fa telling The Post they saw Mandarin as more useful than English. Beefing up Mandarin education is also welcomed by Chinese businesses setting up roots here and struggling to find qualified staff.

“One of the concerns of Chinese enterprises here is that they simply don’t have enough Mandarin speaking staff,” said Murg. “China does bring in its own folks [as employees] on occasion but it is a limiting factor when you have this massive demand and such a limited supply. Hence we see the massive expansion of Chinese education.”

Shi Guanghui, the owner of translation company Guanghui Service, said that many companies now provide Mandarin language training for their employees. The benefits for workers are obvious, Xiulong said. “Cambodian people in the factory get paid around $200 to $300 a month. If you speak Chinese, you get $400 or $500,” he said.

Offering an admittedly controversial opinion, Murg said he believes that in the next decade and a half, Mandarin will become the dominant second language in Cambodia, due to the “sheer scale” of investment. He recalled a recent conversation with a Cambodian friend whose mother had chastised him for sending his 3-year-old son to study English.

“She said, ‘Why are you wasting your time learning English? You should be learning Chinese’,” he said. “That was the first time I’ve had a non-Sino Khmer friend basically say ‘we switched over’. I was surprised – this is real.”

Additional reporting by Rinith Taing