DULUTH, MN (KDAL) - The Duluth Parks and Recreation Department is sponsoring a "School Early Release Day" open skate session on Friday at the Heritage Sports Center.  The session is free and open to the public for pleasure skating from 2 to 4 p-m at 120 South 30th Avenue West.  The Center also features open skating every Wednesday evening from 6:30 to 8 p-m.