Coat the potatoes in coarse salt to help retain moisture.
Wrap each potato in a piece of foil. You do not need to prick them.
Place wrapped potatoes in your crock pot. You can place 10 medium sized potatoes in a 4 quart crock pot.
Cook on low for 8 hours.
Another option: You can cook without foil - prick the potatoes and rub with olive oil. Or add a couple of balls of crushed up aluminum foil to the crock pot mixed in with the potatoes.
Notes
You can also put potatoes in crock pot over night and then slice for home fries the next morning or make them into potato salad.