A short activity using music which prompts discussion.
You'll need a series of short extracts of different types of music – maybe half a dozen extracts with a total length of two or three minutes. Introduce the activity by asking the learners to listen and, as they do so, to draw a graph on a piece of paper to represent the level of interest or involvement they feel.
Then they compare their graphs in pairs or small groups, which will prompt them to share their reactions to the various music extracts, and perhaps to talk more generally about their preferences in music. If they're interested in talking about this, let them continue for as long as it seems useful, but don't force it.
Instead of drawing a graph, they could give each extract a score out of 10, or draw a facial expression to illustrate how they feel about each one.