Hong Kong children can go to school without worrying about their safety, but some mainland students have to be cautious about every step they take on their way to the classroom. Nearly 400 primary students in Maosi village, Gansu province , attend four cave schools on both sides of the Po River, which freezes in winter and can be a raging torrent during summer monsoons. This means students do not go to school from November to February for fear of falling into the freezing water and between May and August because the river is flooded. To make life easier and safer for children and parents, a group of Hong Kong academics have designed a special floating footbridge which will be put up across the river this summer. The construction is expected to begin in June or July and will last about a week. Headed by Chinese University of Hong Kong architecture professor Edward Ng, the project - 'A Bridge Too Far' - is part of a campaign to improve education facilities for the local population. The Hong Kong group will also build six new classrooms on the east bank of Po River to replace the traditional cave lessons. 'We will mainly rely on our volunteers to do the on-site construction. We're still trying to raise the $250,000 needed to send 30 volunteers to the village for 12 days,' said Professor Ng. Currently children wade across the river when the water is warm and water levels are low or, when the water is deeper, struggle across a slippery log bridge. Professor Ng said the original plan was to build a submersible bridge, but the forces of nature proved to be a stumbling block. 'When floods come, the water may transport things such as tree trunks, and destroy the submersible part, so we had to change our design and try to build a floating one.' The change of plan also means a revision of costs, which are still being finalised. 'A heavy bridge is always easier to design and build than a light one. We are trying to build a cheap and simple bridge for the villagers ... a structure that can be easily maintained,' Professor Ng said. The 20-year-old cave classrooms, which only have front doors and a few windows, have lighting and ventilation problems. Extremely cold in winter, they have to be heated by burning coal. 'The new schools are not in the caves, but they will be like caves. We will use packed mud to build the classrooms, so they will be cheap, easy to build and comfortable in the summer,' Professor Ng explained. 'Solar panels will be attached to the roof to provide lighting and heat.' The new 12-classroom 'ecological school', due to be completed at the end of this year, will replace the present four schools and cost about 200,000 yuan ($188,715). The team is still looking for sponsorship to send the 30 volunteers to Maosi village. If you are interested in making a donation, visit www.arch.cuhk.edu.hk/servera/ staff1/edward/www/b2far/index.htm or contact project executive Polly Tsang at 9638 0452.