Illinois' latest standardized test results show that the achievement gap among elementary school students is narrowing, largely because of gains among black, special education and low-income students, the Illinois State Board of Education announced Monday.

The board also said that nine schools flagged for improvement under the decade-old federal No Child Left Behind Act were taken off that status because they made adequate yearly progress for two years in a row. The improvement came even as the state's proficiency benchmarks rose 7.5% over the past two years.

The state board reported that over time, the achievement gap between white and black students has narrowed by 11.4% in math and 7.9% in reading. Since 2006, black students have posted a 14.3% increase in meeting and exceeding proficiency in math and a 13% increase in reading on the Illinois Standards Achievement Test.

Hispanic students also have upped their proficiency on the statewide test, improving by 4.7% in math and 5.2% in reading.

The improvements come as the number of minority students in Illinois' public schools continues to climb, from 36.7% of students in 1997 to 48.6% this year. During that span, the population of the state's low-income students rose from 35.7% to 48.1%.