The subway may be packed with throngs of students and angry parents this week if the city’s school bus drivers make good on their threat to strike. On Sunday, New York City Schools chancellor Dennis Walcott unveiled contingency plans for the 152,000 public- and private-school students who may be affected, while Amalgamated Transit Union members rallied nearby at City Hall. The union is upset with the city’s plan to accept bids for 1,100 bus routes for children with disabilities, which they fear may lead to many drivers losing their jobs in June. “They’re trying to replace us with inexperienced drivers working for new companies for minimum wage,” Samuel Rivera, who’s been a bus driver for nearly a dozen years, told the Associated Press. Walcott insists that any new drivers will receive proper training, and says the union is just trying to scare parents. Unfortunately for the kids, they won’t be enjoying any extra vacation days; the city plans to hand out MetroCards and reimburse parents for mileage and cab fare.