I have been living in Kunming for 5 years. I think Chinese government does know well about their policies and laws.
I have also consulted a Chinese friend of mine, which is a famous lawyer. She said that it is very easy to solve the price increase. Simply contact the government to confirm if the tuition increase is a government order. She said the government pays a lot of attention to affairs realted to foreigners. She also helped us to get these information - The department in government we should consult is Yunnan Education department, foreign cooperation and communication section. The person primary works on this issue is Mr. Li Mao, and his number is 5141238, and the director of this section is Mr. Zhang Shao Hong. Their address is Kunming Xuefu Road 2, Education Building Fl5, close to the Xiaocaiyuan Overpass) 昆明市学府路2号教育厅大楼5楼(小菜园立交桥旁边)。