The Boston Globe has a useful article headlined Watch and learn:How music videos are triggering a literacy boom.
It’s about the use of subtitles in music videos as a tool to teach native-language literacy, and shares some good stories and research.
Many ESL/EFL teachers are very aware of the usefulness of subtitles in second-language instruction, too.
You might also be interested in The Best Music Websites For Learning English and The Best Online Karaoke Sites For English Language Learners.
You might also want to read an interview I did on using music in the classroom.