Chester Bowl in Duluth MN is the sickest hill. Anyone who hits up Duluth should bool here.
http://www.chesterbowl.org/
It's a small, non-profit, locally owned ski hill! Often times I know the moms who work the chalet. The owners of the hill ski with you. They have a freestyle cadet program. And if you get a season pass for the Spirit Mountain, you automatically get a free Chester Bowl pass too. This is skiin at its finest