2018 Milestones Results by Subgroup

The visual below shows math proficiency rates for all students, Black students, and White students at Atlanta Neighborhood Charter (ANCS) and Drew Charter. Notice that differences in overall performance do not necessarily correspond to similar differences in subgroup performance. Drew’s overall middle school math proficiency of 57%1 is eight points higher than ANCS’s rate of 49%. But the proficiency rate for black students at Drew is 43 points higher than the rate at ANCS (50% vs 7%), and the rate for white students is thirty points higher at Drew (95% vs 65%). The overall gap between the two schools is smaller than the subgroup gaps because the school compositions are different.

The drop-down options allow comparisons by district, school, exam, subgroup, and year. Try adding an additional school or subgroup to the graph, or add another year to see changes over time. Mouse-over a graph to view student counts or mouse-over the details button to learn more about metrics and subgroups.

The next graph shows math proficiency rates for Atlanta Public Schools and Decatur City Schools. Notice that proficiency rates for free and reduced lunch (FRL) students are nearly identical between the two districts, as are proficiency rates for not-FRL students. But the overall proficiency rates are very different because the two districts have different percentages of FRL students.

At schools that use the community eligibility provision (CEP), all students are marked as FRL in Milestones reporting regardless of actual status. We estimate that this inflates the math proficiency rate for the APS FRL subgroup by about two points2, but the APS proficiency rate for FRL students is still similar to Decatur’s. At the school-level, this visual does not show seperate proficiency rates for the FRL subgroup at CEP schools.

Data for these visuals is from the Governor’s Office of Student Achievement, found here.

See last year’s post for more context on achievement gaps in Atlanta and for ideas on how to interpret and respond to the data. See the CCRPI subgroup post for more subgroup data, and the school performance and poverty post to learn more about that relationship.

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  1. This measures EOG performance only, so does not included advanced math students who took Algebra in eighth grade. Including eighth grade Algebra I students raises Drew’s middle school math proficiency rate to 59%.
  2. Based on pre-CEP data, the average FRL rate at CEP schools is 92%, so most students are correctly categorized.