FM transmitter for my classroom

[Haopengyou]

I want to buy an fm transmitter to put in my classroom so that I can have a part of the class watch a video or computer website without interfering with what other students are doing. Each of the 15 students will be wearing an fm headset.

I know almost nothing about fm transmitters. How many watts should the transmitter that I buy have? What else do I need to know? The classroom is about 30x20 ft long and has fluorescent lights.

[TreeTops]

I have used FM transmitters to broadcast audio only. If you want to broadcast video I would use a LAN. You can look here for more info: http://news.cnet.com/8301-17938_105-57485724-1/home-networking-explained-heres-the-url-for-you/ It says home networking but you can substitute your classroom for the word home. Not sure you can get all you need in China but you can try.