This is a guest post by Kristin Damo, the founding principal of Success Academy Lafayette Middle School in Brooklyn.

My father emigrated from the Philippines and raised me on his own. The promise he made to me as a child is that I would have access to a world-class education.

Today, this is the promise I’ve made to my son, who I am also raising on my own, as well as to the 70 families who have chosen Success Academy Lafayette as their middle school for the coming year. I am their founding school principal.

Yet Mayor de Blasio is making this promise impossible. Weeks ago, these families decided to enroll their fifth-graders in the intentionally diverse middle school we are forming in Bedford-Stuyvesant. Now, at the last minute, the de Blasio administration has done an about-face and is denying these children an opportunity for educational excellence and equity because of an arcane and arbitrary technicality.

Diverse communities are essential to the fabric of New York City. Displacing students marginalizes them and insinuates that they are not wanted. Our student body is 63% black, 16% hispanic, 16% white, and 5% multiracial/other. Diversity is a delicate balance.

The Department of Education has suggested placing these fifth-graders in a temporary space. This school community needs certainty in the form of a permanent home in order to thrive.

Earlier this month, Mayor de Blasio rolled out a plan to diversify our city’s specialized high schools. In this plan, he talked about bringing “equity and excellence to our schools” and demographics that would mirror those of New York City. He said diversifying our schools would “make our society stronger.”

But now the Mayor is blocking a school that meets those high standards. It seems his plan was just empty rhetoric.

There is no logical reason to evict these children from this building. The new middle school will use exactly the same space as the previous Success Academy elementary school. This will not affect our co-located school, P.S. 25, in any way.

This upcoming school year will be my 12th year in education.  I have worked for both district and charter schools right here in New York, in Washington, DC, and in Los Angeles. I can say with conviction that Success Academy offers an unparalleled education.

When I received the news that I was going to be the founding principal of Success Academy Lafayette Middle School, I was beyond excited. I learned every one of my incoming students’ names. I called their fourth-grade principals because I wanted to know more about them. I gathered a team of the best teachers, who have already begun planning their classrooms and thinking about ways to create an intellectual atmosphere.

So, when Success Academy called me with the news two weeks ago that the city was going back on its word and was going to block the opening of SA Lafayette, I was astounded. Why should it be so hard to create a school in NYC? This year, it will be 70 fifth-graders, and each year, we will add a new cohort of incoming fifth graders until the school fills up to roughly 450 students in grades 5-8.

If Success were failing its children, that might be a reason to halt our growth. But, the fact is, we are not. In the fourth grade, 99% of our 70 students passed the math state exam, and 96% of them passed the ELA exam. But test scores aside, we provide a true education that will create critical thinkers who will learn never to accept what is handed to them at face value, and who will ask questions and challenge unjust decisions.

The Mayor would never announce to district families that their school was closing within weeks of the beginning of the school year. But the children of Lafayette are our kids, and we will not let them fall behind.

Mayor de Blasio, we are demanding fairness. Don’t treat our scholars like furniture — moving them without notice — and respect the choices these families have made. Help me keep my promise that Success Academy Lafayette will be a high point of Brooklyn’s growth in education. On behalf of our resilient students and staff, I urge you to use the emergency powers provided to you to allow our school to open in August.