Tomorrow afternoon at 1pm, supporters of Washington DC Opportunity Scholarships will be rallying in Freedom Plaza to save the school voucher program. Why? That’s easy: Because a federal Department of Education study shows that parents are overwhelmingly more satisfied with it than they are with DC’s public schools. Because the same study shows that the program is raising student achievement above the level in the public schools. Because the children participating in it feel it is giving them a chance to realize their full potential in life — a chance that will disappear if the program is allowed to die, as they have attested in numerous YouTube videos.

The harder question is why Congress — particularly congressional Democrats led by Sen. Richard Durbin (D., Ill.) — want to kill the vouchers. Their stated reason is that it robs money from needy public schools and gives it to private schools that are already flush from lavish tuition fees.

But the voucher program not only does not take money away from DC public schools, the language of the law actually includes an extra $13 million annually for DC public schools, above their normal funding stream. As for lavish vs. needy schools, it’s true that there’s a huge gap between what is spent per pupil on public education in DC and the average tuition charged at the voucher-accepting private schools: a yawning $20,000 gap. The current year budget for the District of Columbia allocates $26,555 per pupil for k‑12 education — up from $24,600 last year. Meanwhile, the Department of Education study linked to above puts the average tuition at voucher schools at $6,620. So vouchers are getting better results at one quarter the cost.

Clearly, Democrats have other reasons for opposing the voucher program, and this letter from the NEA might have a little something to do with it.