D.R. Wagner, a lecturer in environmental design, came up with the perfect Halloween assignment for his Visual Culture and Introduction to Design class: carve a jack-o'-lantern. Nearly 200 students spent about an hour Tuesday afternoon drawing, cutting, scooping and carving their ghoulish creations. Afterward, the students took the pumpkins and lined them up on the sidewalks in front of Walker Hall. "It was fantastic," Wagner said. "The students really got into it." The assignment was designed as a tribute to Dolph Gotelli, professor of environmental design, whose own speciality is holiday decorations.