I usually talk about equivalence class partitioning before the topic of property-based testing. It's useful even for manual testers to think about.
https://en.wikipedia.org/wiki/Equivalence_partitioning
Then I talk about randomly sampling from a partition as a way to eventually detect "hidden" partitions you didn't expect. Like Hypothesis does.
When dealing with many parameters, each with several partitions, the variations multiply quickly. To deal with combinatoric explosion, I talk about all pairs testing, also known as "pairwise" testing.