Two of Ms. Ocasio’s daughters attended P.S. 46 this year: Junie, in first grade, and Olive, in kindergarten. The new students were their classmates, which Junie pointed out on their walk home one day when she recognized a girl with a family holding a sign asking for money for food. The shelter meals were terrible and were making some of the children sick. Ms. Ocasio bought the family a bucket of chicken. Afterward, Junie said, “But Mommy, you can’t buy all my friends buckets of…