In just a little while, Shael Polakow-Suransky, the number-two official in the city Department of Education, will explain his thoughts about the city’s school accountability system should evolve after the Bloomberg administration’s end.

Central under Bloomberg have been school letter grades awarded annually since 2007 to all city schools. (This year’s grades came out last week.) The grades, known as progress reports, reflect students’ raw performance as well as their progress. They also show how schools stack up with other schools that have similar students.

But critics, including Mayor-elect Bill de Blasio, say the grades unfairly stigmatize schools and simplify school quality too much. They have also objected to the fact that about 85 percent of elementary and middle school grades come from students’ state test scores. De Blasio has said he would no longer award schools single letter grades.

Polakow-Suransky’s proposal, which he’ll make at an event hosted by former state education chief David Steiner’s think tank, will likely reveal which parts of the progress report system the Department of Education is willing to see go and which parts it considers essential. A report that he discussed publicly last week was written with the goal of identifying “low-hanging fruit” that could be sacrificed under de Blasio without fundamentally derailing the department’s network structure of school support.

Polakow-Suransky sketched out his vision for accountability in a blog post in September and offered additional hints last week.

“Getting more of that qualitative data that brings in information that can’t be easily captured in state tests is a really important thing,” he told reporters. “It sends a signal to schools that that’s important and that that’s something that we care about.”

Exactly how the department might factor qualitative data into the reports is unclear. It will also be interesting to note whether Polakow-Suransky says it’s important for schools to receive a single letter grade. Arguing that it is would signal that he does not see a possible home for himself in a de Blasio-run Department of Education.