What you see now is money directed at poor kids, defined by need. The powerful argument for this is simple fairness. Families of means can make choices about education. They move to neighborhoods with good schools. They can send their kids to private or parochial schools.
Poor parents have no such choices.
If their local schools are failing, their kids are trapped. Viteritti argues that, properly designed, it can and, to be fair to all, it should. Preliminary indications are that student performance is strengthened. The strongest backers of all are poor minorities. You can't miss the fact that these are the people vouchers would help.