BUFFALO — Many 4-year-olds cannot count up to their own age when they arrive at preschool, and those at the Stanley M. Makowski Early Childhood Center are hardly prodigies. Most live in this city’s poorer districts and begin their academic life well behind the curve. But there they were on a recent Wednesday morning, three months into the school year, counting up to seven and higher, even doing some elementary addition and subtraction. At recess, one boy, Joshua, used a pointer to illustrate a math concept known as cardinality, by completing place settings on a whiteboard. “You just put one...