Try these:
Mrs.Ploni is such a gossip – “Mrs.Ploni is so nice to me and is always interested in what I’m doing”
Zone out – don’t pay attention, and if you’re called on, say, “sorry, I didn’t hear what you were saying”
Change the subject. Mr.Ploni leaves his yard and sidewalk so messy. – “Did you notice that it’s starting to rain outside?”