Guided Shore Excursions is the best way to learn in depth the local culture.

At Greecing.com depending on the region  you can find:

-Thematically targeted half day Shore Excursions,
-Full day Shore Excursions,
-Multi-day Shore Excursions, including accommodation.

Guided Shore Excursions may have additional options for you to select like Lunch, Supplement for single class, etc.