A common activity is to take out words and have students listen and fill in the gap.
I know, I know. Many teachers are against translation. However, it can be a useful tool and it will allow your students to understand the lyrics.
Find songs without words or ones that have words in a foreign language that they don't know. Then have them invent the lyrics. As an added bonus, see if your students will sing them.
Idioms and Slang
Students always want to learn real English, the English they hear on tv, at the movies, or in songs. So here's your chance to explain it to them. Just be sure to look over the lyrics very carefully beforehand and see if they're appropriate. A good activity to use with idioms and slang is matching.
Rhyming Words / Pronunciation
Many songs use words that rhyme. This is especially useful if the spelling is different, but they still rhyme. It's easy to see that words like "cat" and "hat" rhyme. However, it's more difficult to see that "mac" and "coming back" rhyme. You can tie in lessons with spelling and pronunciation.
There are two ways I like to use synonyms in class. The first is pretty straight forward; students have to think of another word to explain a word I choose (usually in bold). The second is a bit more challenging. You can take out words, similar to a gap fill, and have students guess what could go in the blank. You'll have to find a song that students don't know in order for this to work. It's fun to compare what students have chosen to put in the blanks.
You can order the stanzas, sentences within the stanzas, or words within the sentence. Again, it works best with songs that students don't know. When I have students order stanzas, I cut the song into strips. For ordering sentences or words within sentences, I put the mixed up sentences / words on one paper.
Ok, songs might not have the best grammar out there, but there are some good ones for teaching tenses. Take a look at these to get some ideas: ESL HQ and TEFL dot net and TEFL tunes. Looking for more tips on teaching grammar? Check out this article I wrote about grammar.
There are many things that you could use songs to talk about. Things like money, customs, culture, education, fashion, history, relationships, politics, and science are just a couple of ideas. TEFL tunes has a good list.
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