OXFORD, Mich. — Students returned Monday morning to the newly renovated Oxford High School for the first time since a school shooting on Nov. 30 left four students dead and injured six others and a teacher. Snow fell on students from a dark, gray sky as they trickled into the school, preparing to walk its halls and sit in its classrooms nearly two months after the shooting. Across Oxford and nearby Orion Township, signs that read “Oxford Strong” and “Pray for Oxford” still adorned yards, driveways and storefronts. For weeks prior, students attended classes online or at Oxford Middle School as …