# Fuzzy Math

##### By Arnold Kling

Upon the debut of the Maryland School Assessments in 2003, Montgomery County ranked second in the state in math, with 67 percent of students passing tests in elementary and middle school. This year, the county ranks 11th.

The reporter proceeds to make a series of excuses. First, the pass rate has gone up to 82 percent in our County. It has just not gone up as rapidly as in other Maryland counties.

The county also has its share of disadvantaged students. Montgomery has the largest proportion of students with limited English proficiency, 12 percent, of any school system in Maryland. The county ranks 14th poorest in the share of students qualifying for meal subsidies by virtue of low family income, 27 percent. Both measures have risen since 2003.

Does anyone know how to get hold of this data? If so, then I have a simple suggestion for how to present it on a chart. On the X-axis, plot the percentage of students in a county who are above the FARMS line (that is the “free and reduced meals” indicator of poverty). On the Y-axis, plot the percentage of students that pass the math exam. For each county in Maryland, put a data point on the chart. Next to each data point, put the County’s ranking in terms of expenditure per pupil.

Next, draw the line of best fit through the data points. Counties that fall above the line are adding relatively more value than counties below the line. If education spending matters, then Montgomery County and other high-spending schools should be above the line. It would be interesting to see whether this is in fact the case.