Is there any public transportation between S Jersey (Penns Grove) and Christaiana Mall or Wilmington?
If there is, I can't find it. There apparently used to be a NJ Transit bus that served Penns Grove and went to Wilmington (Route 423) but it's no longer listed on NJ Transit's own website, so I think you are out of luck.
Although Wilmington and Penns Grove are not even 5 miles from each other as the crow flies, it seems like the only public transit option is to get yourself from Penns Grove to Philadelphia (Market East) via NJ Transit Bus 402, then take the SEPTA subway from Market East to 30th St., then SEPTA Regional Rail from 30th St. to Wilmington. And if you wanted to continue on to Christiana Mall, that would mean another bus (DART, several routes). This would take the better part of a day all together...a giant waste of time.
Rent a car or find someone to drive you!
I can't find one either. Guess I'll be shopping in NJ or Philly. Thanks for your effort. Kind regards, B