Three Hamilton County schools and three Bradley County schools are among those impacted by a TNReady scoring error.
State education officials believe nearly 10,000 assessment tests across the state were scored incorrectly.
In Chattanooga, Red Bank High School, Lookout Valley Middle/High and Ivy Academy were affected, according to school officials.
In Bradley County, the schools affected were Bradley Central High School, Walker Valley High School and Bradley County Virtual School, Linda Cash, director of schools, said in a statement.
The only subject effected was Integrated Math 2. The scoring error involved 402 students but only 55 students had corrections that changed their performance levels.