Chicago Public Schools, the third-largest U.S. education district, will resume in-person classes on January 12 after a union decided to end the walkout over COVID-19 fears in an agreement it said would boost safeguards. Last week, teachers began their action, idling some 340,000 students, following a union vote to reinstate virtual instruction and a push for more rigorous safety protocols, including wider testing, as the Omicron variant spread.