The cost of textbooks under the new senior academic structure has risen, with some publishers nearly doubling the prices for certain subjects. The fewer subjects required to qualify for the future Hong Kong Diploma of Secondary Education examination, which will replace the HKCEE, meant longer lesson times per subject, which would translate into thicker textbooks, the Educational Publishers Association said. Compulsory Form Four subjects under the new system, including Chinese, English language and mathematics, registered an average increase of 8 per cent - with prices for English-language textbooks rising 12.3 per cent. The average prices in elective subjects such as geography (HK$401), physics (HK$510) and economics (HK$414) have also gone up. Biology textbooks will cost an average of HK$476 - an increase of 87 per cent on last year's HK$255. The Education Bureau released the prices of books for senior secondary subjects yesterday after assessing 152 sets of textbooks submitted by publishers. A parent of a Form Four arts student will have to pay an average total of HK$2,638 for textbooks in the forthcoming academic year, while that for a science student will amount to HK$2,849, the association said. The increases were due to curriculum changes in the new senior academic structure, said Elvin Lee Ka-kui, the association's secretary. Four subjects - Chinese, English language, mathematics and liberal studies - will become compulsory, while two or three electives may be chosen from 20 subjects. Mr Lee said publishing houses had to employ many extra staff to prepare the new set of textbooks. 'There's an average 50 per cent increase in personnel,' he said. Shek Kwok-kei, the association's president and a publisher with Pilot Publishing Company, said it was impossible to compare new senior secondary textbooks with those for the past academic year. 'Students now have to take eight or nine subjects' for the Hong Kong Certificate of Education Examination, Mr Shek said. 'In the future, they just need to take six or seven subjects. 'The decrease ... entails a longer lesson time, which means textbooks will be much thicker than before. Take English as an example - the current number of teaching hours is 270, which will be increased to 405 under the new structure. That's why the average number of pages for an English textbook has risen from 432 to 1,700.' There was room for textbook prices to go down, said Cheung Kwok-wah, principal assistant secretary in curriculum development with the Education Bureau. 'We have suggested cost-saving measures for publishers, such as using cheaper paper and uploading activities onto the internet instead of printing them out,' Dr Cheung said. Connie Lau Yin-hing, chief executive of the Consumer Council, said publishers should refrain from using luxurious methods, such as banquets, to promote textbooks. Both Dr Cheung and Ms Lau said it was impossible to compare prices at this stage. 'We don't know how the schools will choose subject combinations,' Ms Lau said. 'After the schools make their choices, we will do a study comparing their prices.'