Thanks as much to their parents’ incomes and education levels as to what happens in the state’s classrooms, New Jersey students have a better shot at success than children in all but three other states, according to the Quality Counts study from Editorial Products in Education. While New Jersey has extremes of wealth and poverty, it has the highest median household income. And its adults, on average, are well educated. More than half the state’s children have at least one parent with a college degree and three-fourths of children have at least one parent working a full-time, year-round job. Those factors all give children a better chance of succeeding in college or the work force, the study said. Like many studies, it praises New Jersey for its graduation rate, which was nearly 85 percent according to the 2003 data it analyzed. Like many studies, Quality Counts found the gap in test performance between poor students and others is wider than most other states but also closing faster than most. Last fall, the Thomas B. Fordham Foundation’s look at education of needy children gave New Jersey a “D-plus” for student achievement. But the grading curve was tough in that study; it found only five states were doing better. New Jersey schools received a middle-of-the-pack “C-minus” for school reform.