My chapter didn't have a philanthropy day when I was there, Rush was only 3 days (1200 people in the school, who needs more?) but since Rush wasn't until the middle of January, we had pre-rush events open to all women on campus in the fall.
In October, the chapter sells homemade caramel apples at the Homecoming game, and the proceeds go to the local domestic abuse shelter. A few years ago, we decided to combine the apple-making with the pre-Rush event. The actives and PNM's make the apples together in the kitchen of the Panhel wing (no houses, but we have our own wing in a dorm). It's messy but fun and tasty. Even more fun is going to the apple orchard with other sisters and picking the apples.
Favorites included the chocolate-and-peppermint covered, as well as the standard nut, caramel, chocolate, etc. I'd recommend Macintosh apples (the only kind I eat
).