Here is a Cultural Literacy worksheet on Cassandra, she of Greek myth. She is often a metaphor, in polite but educated conversation, as a metaphor for a person whose valid warnings or concerns about the future are disbelieved by others.
If you find typos in this document, I would appreciate a notification. And, as always, if you find this material useful in your practice, I would be grateful to hear what you think of it. I seek your peer review.