The connection between poverty and test scores seems so enduring that many people talk about it as if poverty is prophecy.
That point is easier to make when you look at "point-in-time" snapshots of proficiency rather than looking at student growth. With the release of 2017's NAEP scores some researchers offered novel, nuanced takes on the results.
Correlation coefficients range from -1 to 1, and those closer to zero, like -0.13, generally signal weak relationships. In this case, the weak correlation means that third graders in districts with high average reading and math test scores will not necessarily see bigger (or smaller) gains by eighth grade than will third graders in lower-scoring districts.
If your belief is that the school system exacerbates inequality—that the advantaged districts that start with high achievers strongly accelerate the educational growth of their students, whereas students of lower-achieving, disadvantaged districts are destined to meager growth—you might have guessed that such a correlation would be strong and positive.
If you believe that schools function as a great equalizer, you might have expected a stronger negative relationship.
If you believe in the remaining option, however, that school systems consistently mirror the inequality occurring outside of school doors, that is not quite right either.
The relationship between early achievement and subsequent gains is not weak because districts consistently maintain inequality that is brought to their doorstep, but because school districts’ impacts on student gains are inconsistent. As the study’s author, Dr. Sean Reardon, states, “the role of schooling in shaping educational opportunity varies substantially across places.”
In other words, the answer to the question of whether school districts decrease, replicate, or increase inequality is “Yes.” Or, more precisely, it depends on which district you are talking about.