By Tom Brown (click here for the PDF)
Look for a home today on most major real estate portals, including Zillow, Redfin, Realtor.com, and Homesnap, and you will find the public schools assigned to each home, along with school ratings. The third-party website that provides these ratings is the non-profit organization GreatSchools.
Though GreatSchools ratings have changed significantly over the years, they are still based primarily on test scores. For elementary and middle schools, the ratings are approximately 30% based on average test scores, 40% on an “Equity Score,” and 30% on test score growth.
The Equity Score primarily measures the achievement gap of each school by evaluating the difference between the average test scores for children that are considered disadvantaged and those that are not. If there is a wide gap, the school gets downgraded under the theory that the school is not doing enough to serve disadvantaged students. “While many schools are having success at closing the achievement gap, and these efforts are important, this gap is a product of several societal factors; arguably the least of which is the school itself.”
Another 30% of each school’s rating is proficiency. But research has shown that test scores are at least 70% attributable to parent income, not school quality. GreatSchools does not consider the socioeconomic context of a school when evaluating its test scores, and consequently, their test score ratings are more informative about parent income than anything else. As a result, their ratings perpetuate a damaging narrative that positions schools with high parent incomes as the “best schools” and schools with diverse or moderate to low parent incomes as the “worst schools.” Low school ratings in neighborhoods with histories of inequality do not merely reflect that inequality; they help drive it.
GreatSchools’ recent inclusion of test score growth measures is a step in the right direction, but using scores with no context of parent income limits any substantive comparisons of student test performance between schools.
At SchoolSparrow, we’ve created a school rating system, rooted in data science, that accounts more directly for parent income. SchoolSparrow’s rating algorithm is a non-linear regression that calculates the average expected score on the Reading Language Arts (RLA) section of the standardized test based on control variables such as the percentage of children considered economically disadvantaged (ECD) that took the test and the percentage of children classified as having a disability (CWD) that took the test.
Our ratings recognize individual schools for their effective teachers and student support staff by revealing the extent to which the school community, not socioeconomic status, is influencing student performance on standardized tests. And they recognize entire neighborhoods and cities as desirable destinations for parents searching for a quality education for their children.
Realtors report anecdotally that parents want a 7/10 rating or better in their children’s schools, particularly if they are moving to a new city. If the schools associated with the home they want to buy have a rating under 7/10, they often dismiss the school and the neighborhood that the school serves. But if those parents consulted SchoolSparrow school ratings, they might make different decisions. To illustrate what we mean, let’s look at Berwyn, Illinois, and University City, Missouri.
Berwyn is a suburb of Chicago located south of the affluent suburb of Oak Park. During rush hour, the drive to the Chicago CBD is roughly 30 minutes, but Berwyn has transit locations with a short 20-minute train ride to downtown Chicago. The average single-family home value in Oak Park is $491,000. The average single-family home value in Berwyn is $282,000.
GreatSchools rates five out of 13 public schools in Berwyn a 7/10 or above, with an average school rating of 5.8/10. SchoolSparrow’s rating system, on the other hand, rates 11 out of the 13 public schools in Berwyn a 7/10 or above, with an average school rating of 7.4/10.
Student performance on standardized tests when compared to similar populations of students is above average in 11 out of 13 public schools in Berwyn. According to SchoolSparrow’s model, more than half of Berwyn’s public schools are underrated. The major real estate search platforms unfairly portray six of the nine public elementary schools in Berwyn, which depresses both housing demand and home value, and can lead to increased economic segregation.
University City, Missouri
The U.S. Department of Education reports that 100% of students at all public schools in University City, Missouri, are considered economically disadvantaged. There are six public schools in University City, all of which have ratings of 6/10 and below according to GreatSchools, and five out of six of the public schools have ratings of 4/10 and below.
But when standardized test scores are analyzed in the context of schools’ socioeconomic context, we can tell a much different story for University City’s schools. Four out of the six public schools in University City have ratings of 7/10 or better according to SchoolSparrow, including a 10/10 for Flynn Park Elementary and a 9/10 for University City High School (rated a 2/10 by GreatSchools). SchoolSparrow’s higher rating is because the predicted average reading score (30%) is lower than the actual score (42%) – meaning they overperformed compared with the schools with similar populations in the state. University City’s schools are out-performing expectations on standardized tests, but today’s dominant rating system is standing in the way of these being recognized as high-quality schools.
Some have expressed concern that recognizing these schools could have damaging impacts in terms of aggressive gentrification. Both University City (MO) and Berwyn (IL) are relatively affordable communities when it comes to home prices. We acknowledge that gentrification could change these dynamics but believe that today’s ratings that obscure many exemplary schools can exacerbate the problem more than a system that provides more nuanced information about school quality.
Measuring School Quality
Test scores are not the most important factor when it comes to evaluating school quality. Things like school safety, teacher morale, and an inclusive culture are at the top of the list for many parents. But if you must consider test scores, SchoolSparrow believes that it is important to share as many details as possible about how a school community, not the socioeconomic background of its families, influences student performance on standardized tests.
SchoolSparrow aims to build a data set and allow users to create their own customized rating system based on what they believe is important when selecting a school. One parent might weigh teacher quality measures at 50% and parent satisfaction at 50%, and we’ll show school ratings in that context. And if another parent wants to weigh test scores, then they will always see test score data in the context of parent income.
After we’ve created this system, we’ll be able to assign school ratings that point to strengths. One school might be rated in the top 10% of schools in its state based on parent income adjusted test scores, so they are a 10/10 school. Another school might do poorly on tests, but when parent satisfaction and attendance are considered, the school is in the top 20% of schools in the state, so that school is a 9/10. When parents click on the rating, we will be transparent about how we came to the rating, and parents can start to customize their own personal rating system with a more comprehensive view of what makes a school high-quality for their children.
Implications for Schools,
Neighborhoods, and Cities
Today’s school ratings fail to account for the powerful connection between test scores and parents’ socioeconomic status. Consequently, the school rating system you find when searching for a home online misrepresents thousands of public schools nationwide. In fact, an entire city can have unfairly underrated schools. This negatively impacts the perceived value proposition of a city, and ultimately the home-buying decisions of families. The economic impact on the city, including its families and small businesses, can now be understood and addressed by municipalities by, for example, working towards controlling the narrative of their underrated public schools. ▀
Tom Brown (email@example.com) is the Founder and CEO of SchoolSparrow.com.
Tagami, T. (2018, April 12). Follow the money: the story behind test scores on national exam. The Atlanta Journal-Constitution. https://www.ajc.com/news/local-education/follow-the-money-the-story-behind-test-scores-national-exam/916fIOZXT6ofxpPoDiVm9M/