School children have their bags weighed by members of the Democratic Alliance for the Betterment of Hong Kong. The party's survey of 188 pupils yesterday found that three out of four had overloaded bags. One Primary One school girl was loaded down with an eight-kilogram school bag - two-thirds her own weight. Health guidelines say that bags should not exceed 10 per cent of a child's weight. Lau Pui-ka, 11, who had 20 books in her bag, said: 'My mother has asked me not to take so many. But every book I packed today is useful.'