A student was playing timpani before his lesson, so I told him to stop, because they are not his and are expensive [and apparently being rented from the Minnesota Orchestra]...
Student: How hard can it be to make timpani? It's basically a giant bowl of cereal with a lid on it.
I have been teaching music across the Twin Cities since 2011. Along with seeing students grow as musicians and people, one of the joys of teaching is the ridiculous things my students say.