Can I change my Tourist L to a Resident visa while in China?

I teach for Zhejiang Ocean University in Zhoushan. I arrived on a Tourist L, which expires on January 15th. Can I have it changed to a Resident type while I am here in Zhoushan? I've been told that I have to apply from my home country (USA), but I have also heard I can accomplish this without leaving China. Which is correct???