Why Do DOD Schools Have Good Test Scores?

Schools run by the Department of Defense have very good test scores compared to the public schools in pretty much every U.S. state.

Why is this so?

K-12 school test performance consistently tracks parental education and socio-economic status, etc. It has little to do with how the education process is conducted as opposed to who the kids the system has to teach are. In U.S. military base schools: 

(1) none of the service member parents are in the bottom 30-40% academically and none of the service member parents are high school dropouts – few of the non-service member parents are either due to assortative marriage trends, 

(2) none of the parents have serious criminal records (disciplinary problems are far more hereditary than you think); 

(3) the proportion of kids with very low academic potential/IQ and learning disabilities are far below the general population and that means that teachers don’t have to devote disproportionate time to meeting the needs of these kids, 

(4) few kids are “gifted” (since few parents are selective college material) and “gifted” kids also takes disproportionate time from teachers away from meeting the needs of “regular” kids in regular comprehensive schools, 

(5) the share of kids from married two parent households is much greater than in the no college parents demographic generally, even if the service member parent is absent for prolonged period of time, because military pay strongly incentivizes marriage and having kids; 

(6) no kids lack health care, are homeless, lack food, or are in sustained poverty (basically, the U.S. military is a socialist economy, with both the good things and the bad things that come with that); 

(7) few older kids have to work, or can even find work with all the moving around that they do, 

(8) all kids have at least one fluent English speaking parent and most have two and all have predominantly native English speaking peers in school, and 

(9) most kids will eventually have at least one parent with some college.

These factors are much more important than anything having to do with the Department of Defense school's methods of instruction. One should not take seriously, given this fact, the claim that it matters much that:

Consistent with military culture, they set high standards and create a disciplined classroom culture. In 2015, the schools overhauled their curriculum using principles from the Common Core, a national program that many other districts have abandoned after criticism from both the political right and left. But the approach seems to benefit students. “Unlike the Common Core, which was carried out haphazardly across the country, the Defense Department’s plan was orchestrated with, well, military precision,” Sarah writes.

The fact that these schools are reasonably well funded doesn't hurt but probably isn't pivotal. 

Likewise, the fact that they are racially and economically integrated aren't bad, but probably isn't a key factor. And, while DOD schools are indeed racially integrated, a key to their success is actually, as noted above, that they aren't really economically integrated. They are far fewer children from poor families than public schools do, and have fewer children from very affluent families than public school do. Disproportionately few children educated in DOD schools are in "the 1%" or even the top 5% of income or wealth.

I do believe that it is likely that the good performance of DOD schools in the face of the difficulties of the COVID pandemic may have something to do with how they were run at that time, however. DOD schools improved or held steady at a time when public schools saw declining test scores due to instructional glitches caused by the pandemic. If you want to use DOD schools as a model for anything, look at that aspect of  their instructional approach.