Success Academy parents, staff and students are holding a rally at Roy Wilkins Park in St. Albans, Queens, on Sept. 26 in a desperate bid to get City Hall and the Department of Education to keep their word and provide space for a new Success middle school in the borough.

Team de Blasio promised the space two years ago, then last year asked for a one-year delay — and now the DOE is stonewalling completely.

Without fast action, it’ll be impossible to open the new school in fall 2020 — and up to 200 kids now attending some of the top elementary schools in Queens will be robbed of the chance to continue in the Success program, with hundreds more robbed each year after that. Those children will be stuck with the regular system, which fails to teach more than half its students enough to be proficient in English or math.

For years, Success has expanded by starting a new K-4 elementary school, first with K-1, then filling it out to all classes as kids move up. Then, when the time comes, it needs to open a new middle school (grades 5-8) for every two or three elementary schools — and, four years after that, a high school for every few middle schools.

Charters are public schools, taxpayer-supported and open to all comers. And they (with a few exceptions) rely on the DOE to provide classroom space just as it does for the regular public schools.

With student bodies that are mainly black and Hispanic, Success already runs three or four of the 10 best elementary schools in Queens, as measured by how many students pass state English and math tests, and one of the top five middle schools. Letting it open the new school is a clear win for the borough, for the kids and for the city as a whole.

At least five public school buildings across Queens have ample room for the new school, with 450 to 725 empty seats each. But the de Blasio DOE regularly invents reasons it “can’t” assign such space to charters. And now it has literally stopped returning calls from Success officials about the Queens crisis.

The Success Network has gotten by for a couple of years by squeezing kids into the middle schools it already has in Queens, for example, by temporarily eliminating its art and science rooms. But it has reached the breaking point.

That means that dozens upon dozens of families face the grim task of trying to game the regular system for their children’s entry into a good middle school — which, if they succeed, means some other Queens child will get dumped into a weaker school.

Why pit loving parents who care about their children’s education against each other? Especially when there is literally no need to do so?

Why limit the number of good middle schools (indeed, the number of good schools of any kind), in Queens or anywhere else?

The whole borough should be demanding action from Mayor Bill de Blasio and Schools Chancellor Richard Carranza.