In a laboratory, Christina Lo Lai-ting is the only girl among the boys working on their experiments. The 17-year-old at King's College in Sai Ying Pun is among the last batch of girls attending boys' colleges as a tradition ends amid senior secondary reform. With secondary schooling reduced from seven to six years after implementation of a new senior secondary system in 2009, the sight of Form Five girls switching to another school for matriculation studies is being consigned to history. Under the old system, there were many girls' schools but some did not offer science classes at matriculation level. From Form Six, the girls had to move from their schools to study science at boys' schools. Nancy Chan Woo Mei-hou, the principal of King's College which has enrolled girls for Forms Six and Seven since 1951, said: 'We had 70 girls at the two levels [in the 1950s], but there are only five this year. 'New schools built recently are mostly co-ed schools. Co-ed and boys' schools always have science subjects.' King's College is one of five local boys' schools that still have girls studying Form Six under the old seven-year secondary system. The other four are St Joan of Arc Secondary School, St Paul's College, Kwun Tong Kung Lok Government Secondary School and Newman Catholic College. Christina, the only girl in a science class, said she was nervous at the beginning when she switched to an all-male school upon Form Five graduation. 'I did not know what to say to the boys,' she said. 'I only adapted to the all-male atmosphere after a month.' Karen Ho, 17, who is the only girl in another science class and switched from St Clare's Girls' School to King's College, said she was stumped by the laboratory work. 'My former school didn't put much emphasis on lab work.' In spite of the pressure to excel in class, Christina said she now liked studying alongside boys. 'They will take the initiative to talk to me and we play badminton and ping pong together.' Emily Lam Lee-hung, 18, who switched from Cheung Chau Government Secondary School to King's College, said there were some regrets that the tradition would soon be consigned to history. 'But I love sport and playing video games, which gives me chat topics with the boys. They were surprised that I know how to play football and the fighting video games.' Cherry Tam Lok-ching, 18, said the only odd sight in the classroom was the feminine decorations amid an all-male environment. 'Every class has to decorate their boards for competitions. Girls are entrusted with the job as we are considered more artistic and meticulous with details. The end product is a board filled with girly colours like pink and purple.' Chan said the tradition of accepting girls for senior forms was good for the school's development. 'Interacting with girls can enrich boys' social skills,' she said. 'A former graduate told me he didn't perform well in a public oral exam as he found it hard to listen to the rapid and high-pitched delivery of a girl candidate.' Under the new senior secondary structure, the pupils at boys' schools will now progress from Form One to Form Six, but there will not be any more girls.