There’s something in those Mercer Island house prices: school test scores. I came across this data on the Federal Education Budget Project site by the New America Foundation. They give you data in tabular form, so I used Tableau to create some interesting visualizations of Puget Sound school districts:
The NCLB scores are defined “according to state-defined proficiency standards,” which makes me think they’re WASL scores. One can absolutely question the WASL as a measurement of student success, but for comparing district by district it should be fine since students throughout the state take the same test every year.
So that first visualization shows that yes, Mercer Island Schools are at the top of area schools in terms of test scores. Now let’s look at some factors that go into test scores: poverty and funding.
Mercer Island has the highest math scores, but also one of the largest per-pupil expenditures at $8,357 (Seattle is the only district with a higher per-pupil figure, at ($9140). Mercer Island gets less of its budget from the federal government than any other district, at 2.9% (the average is 5.7%). And out student poverty rate is lower than all but Issaquah.
This data doesn’t do much more than reinforce the well-known link between affluence and school performance. Higher poverty rates make schools’ jobs more difficult. Federal funding helps, but doesn’t fill all the gaps. We’re lucky to live in Mercer Island but we’re part of a larger region as well, and not all kids in the region are getting the same public education.