What do you do when you don’t have enough room to build a running track? How about you take the same approach that has been undertaken by an elementary school in China? The school is located in Tiantai at Zhejiang Province and houses a 200-meter running track. The track has been built on the roof of the school.
School authorities were pressed for space and not having any land to construct the running track on led them to opting for the roof. Chief architect Ruan Hao said, “Under the circumstances that limited land cannot provide enough space for students to exercise in, we chose to challenge the concept that playgrounds and tracks have to be on the ground.” The design has gone famous all over the world and even represented China at the 14th Venice Architecture Exhibition this year.
The track caters to the needs of 1,600 students easily. It has been equipped with a number of safety measures. Three protective layers have been incorporated for the safety; the outer edge has a 6-ft glass wall while the inner wall is 4-ft tall and features a green belt sandwiched between the two of them. Surveillance cameras have also been installed to monitor student activity. 
http://www.youtube.com/watch?v=zRpd2_BROUY