In a library room with bare shelves, Lynn Zwerling dumped balls of yarn, needles and scissors onto two folding tables and sat down to knit with her class. A new student entered the room: peach fuzz on his chin, temple fade haircut, wearing a gray Department of Corrections sweater. As he sat across from his 20 classmates, Reggie Della, 55, told him to “pick up some yarn and needles.