A Form Six pupil yesterday became the first to be tested in a trial drug-testing scheme being launched in Tai Po schools as officials sought to drum up support for the trial, but doubts remained about its effectiveness. Pupils of the district's 23 secondary schools received a pamphlet, a consent form and instructional DVDs about the voluntary scheme and were asked to return the form by November 30. Chief Executive Donald Tsang Yam-kuen appealed to pupils and parents for support of the scheme - relating the story of a mother who went temporarily blind in distress over her son's use of drugs before he finally gave them up. In an open letter, he said the sole aim of the scheme was to help pupils resist the temptation of drugs and 'nip the problem in the bud'. To help launch the scheme, a pupil at Carmel Holy Word Secondary School, identified only as Chow, had a urine test. She said she was nervous as she had never given such a sample before, but 'felt all right about it with the support of friendly nurses'. Undersecretary for education Kenneth Chen Wei-on said he believed the voluntary scheme could support pupils who did not use drugs to continue their healthy lifestyle and encourage those who did to seek help. But he refused to give the number expected to consent to the tests, saying only that most of the 25,000 people who had attended talks on it in the past had been supportive. Registered social worker Eric Tam said the scheme gave parents a 'platform to talk about the issue'. 'A lot of the times, kids make mistakes because of a lack of communication,' he said. Tai Po parent Carvis Cheng agreed. 'You can't ask [children] out of the blue whether they're taking ketamine.' Some, however, continued to question the effectiveness of the scheme's voluntary nature. Lam, a Form Four pupil from another school in Tai Po, said neither he nor his parents would consent. He felt that the scheme was a waste of resources. Yeung Pun-lap, deputy principal of a school in Tai Po, expressed similar views, saying it would not catch drug-takers and was useful merely as an educational campaign. Writing to pupils, the chief executive said the scheme might cause some minor inconvenience but it would 'engender a 'say no to drugs' culture on campuses'. Addressing parents, he said the mother who went temporarily blind did not give up and sought help from teachers and social workers. 'The prodigal son repented and got out of drugs eventually,' he said. In a survey by the Secondary Students' Union of 1,027 Form One to Seven pupils in October, respondents were about evenly split for and against the scheme. About 44 per cent said they were against testing, 61 per cent thought pupils would cheat when taking the tests, while 72 per cent were angry that the government had not consulted them.