Walton High School posted the highest math score of any high school in Cobb County on the 2025-26 Georgia Milestones, and Lassiter High School earned the top spot in U.S. History, the Marietta Daily Journal reported Thursday, Aug. 6.

The scores arrived three days after the new school year began Aug. 3, giving East Cobb families concrete evidence that their neighborhood schools are outperforming the rest of a district that already leads metro Atlanta.

The high school Milestones scores reflect students entering ninth grade, not the full student body at each school. At Lassiter, more than 94% of those students scored at levels 2-4 in every category tested, including social studies, science and math, according to the Cobb County School District. Walton and Pope High School each cleared 90% in every subject. Students who stay at Walton or Pope for all four years graduate 100% of the time; Lassiter's four-year rate is 99.7%.

Cobb outpaces the state

Districtwide, 82.1% of Cobb students scored at levels 2-4 across all subjects and grade levels. That topped every metro Atlanta district, including Fulton County at 81.1%, Gwinnett County at 78.8% and DeKalb County at 61.6%.

The biggest single gain came in high school algebra, where Cobb's average score jumped 11 points, from 339 to 350. Fifth-grade math rose eight points to 342, and eighth-grade social studies climbed eight points to 349.

Scores increased or held steady in 12 of 13 categories. The lone dip: high school U.S. History fell two points districtwide, from 342 to 340.

What the numbers mean

Georgia Milestones measures student learning across four achievement levels, from Beginning Learners through Distinguished Learners. Students at level 2 and above are considered on track toward grade-level proficiency.

Seventy-five Cobb schools had 90% or more of students scoring at level 2 or higher. Twenty-two schools recorded gains of more than 10 percentage points in at least one subject.

"When parents send their children off to school, they want to know their children are receiving the best possible education," Cobb Schools Board Chair Randy Scamihorn said in the district's announcement. "Rankings don't tell the whole story, but they do confirm what parents know: our Team is delivering that high-quality education, while protecting the taxpayer's dollar."

What's still to come

English Language Arts scores were not included in the Aug. 6 release. The Georgia Department of Education said new K-12 ELA standards required additional test development, and those results will follow later in 2026. No specific date has been set.

Walton's school year is underway at 1590 Bill Murdock Road in Marietta.