Falling student enrolment is now hitting secondary schools which are facing growing numbers of surplus teachers. The Subsidised Secondary Schools Council wants the government to extend the early retirement scheme to the secondary sector. The number of classes has fallen by 135 over four years and is expected to further fall, according to the Professional Teachers Union (PTU). Based on the class-teacher ratio of 1:1.3, there are more than 130 surplus secondary teachers. Dominic Chu Fu-yan, chairman of the Subsidised Secondary Schools Council, which represents more than 70 per cent of secondary school principals in Hong Kong, said their teachers were now facing growing job uncertainty. 'The impact of falling birthrate, which has been hitting the primary sector hard, is now reaching secondary schools,' Mr Chu said. 'The situation is expected to get worse with senior secondary reform, which will reduce four years of senior secondary education to three. We need a way out for teachers before things get out of hand.' The PTU is backing the council. Cheung Man-kwong, the union's president, agreed that the government should extend the early retirement scheme but added that a reduction in class size in primary and secondary schools would be the best alternative. In the primary sector, the number of classes is down 136 this year. A total of 611 primary teachers have opted for early retirement, receiving a total of $173 million, according to Education and Manpower Bureau figures released this week. Their average age is 52, with only 178 educated to degree-level.