CONSTRUCTION starts soon on a $150 million Japanese International School in the New Territories. It will be built on land provided by the Hong Kong Government at Tai Po, close to the Chinese University. The school, for 800 primary pupils aged between six and 11, is scheduled to open in 1997. Six of the 18 classes will be for non-Japanese pupils studying in the English stream, according to Katsuyuki Kitagaki, the director of community relations. 'The school is needed because the existing one is overflowing,' he said. There are already two Hong Kong-Japanese schools on Hong Kong island - a primary school with 1,600 pupils in Blue Pool Road, Happy Valley, and a secondary school with 400 students at Braemar Hill. But a third school was desperately needed because both had reached capacity, Mr Kitagaki said. One explanation for the popularity of the Japanese international schools is the fees, which are among the lowest in Hong Kong. Primary school fees are currently only $1,200 a month, while the secondary school charges just $1,300 - a quarter the price of educating children with the English Schools' Foundation and most other international schools. 'We can afford to keep the fees low because our government subsidises the teachers' salaries,' Mr Kitagaki said. 'But we are going to have to put the fees up at the new school - although it has not yet been decided by how much.' The Japanese community has been growing every year and now numbers more than 20,000.