School testing: An actuarial analysis, Part 3

[Ed. note: In this series, I use actuarial techniques on data behind the Nation’s Report Card, a regular testing of 9-, 13- and 17-year-olds, to argue that:

  • The gap between white and black students has been declining and will continue to decline.
  • Whatever gap exists is in place by the age of 9 and stubbornly resists change thereafter.

Part One is here. Part Two is here.]

The first graph looks at the gap in reading scores for 9-year-olds born between 1962 to 1999. (Remember the years represent the years the kids were born. They were tested nine years later.)

Reading gap: shrinking

The gap starts at nearly 45 points for kids born in 1962. It declines steadily until we get to kids born between 1979 and 1993, then steadily declines. At last report, the gap is under 25 points.

So whatever steps we’re taking up to age 9, they seem to be working. It’s after this that the results get discouraging, if you look at the data as it has been traditionally been presented. Black students “give back” the gains they made through age 9.

Looking at the data by cohort, a different story emerges.Now, let’s see whether the gains achieved by age 9 evaporate – the conventional wisdom, if you will. Remember, we couldn’t do this before we put together the “actuarial” data set, since we didn’t have the same cohort tested at 9 and 17. Now we can compare how much white kids’ scores improve between 9 and 17, then compare it with how black kids do.

No progress.

On this graph, if the line is above zero, it means that white kids have advanced farther than black kids. A number below zero means the opposite.

Until the kids born in 1966, white kids advanced a little farther than black kids, but not by much – less than five points. For cohorts between 1966 and 1971, black kids outperformed white kids by increasing amounts. Since then, black kids have done a bit better, but not much.

There’s no evidence that black kids “give back” the gains made at age 9. If anything, they close the gap a little more.

In fact, the striking thing about this graph is how closely white kids and black kids progress through these eight years of schooling. The gains that white kids have early in their education stay with them throughout.

This makes sense, when you think about it. Were some teacher to invent a revolutionary teaching method, that method would probably work equally well on any kid, regardless of race. For black kids to catch up between 9 and 17, they would have to exclusively enjoy that educational method for a prolonged period. And our education system isn’t set up to work that way.

The story with math achievement is pretty much the same.

Improvement here.

This story is similar to what we saw with reading: significant improvement until 1977, movement in a narrow range till the group born in 1995. It’s not as clear here that the breakthrough will maintain itself.

And here’s how the achievement gap has changed:

Not much change here.

The story is slightly different in math vs. reading. Black students improved more than white students till about 1979, then the situation turned.

But the differences are fairly slight. Again, there’s no evidence that black students “give back” the gains made by age 9.

The prescription here seems clear: If we want to reduce the gap between black achievement and white achievement, we need to do it by age 9. There’s evidence that black students can close the gap up to that age.

Whatever gaps emerge by age 9, though, will likely remain.


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