JACKSON— A national sampling of eighth-graders’ performance in science showed Mississippi with a small improvement from 2009 to 2011 but still below the national average.

The National Assessment of Educational Progress report released Thursday showed the average score of eighth-grade students in Mississippi at 137 in 2011, five points better than the 2009 score but 14 points below the national average of 151.

Only 19 percent of students in Mississippi performed at or above the NAEP “Proficient level” in 2011 — low, but an improvement over the 15 percent measured in 2009. Forty-seven percent performed at the “basic” level, up from 41 percent in 2009.

Blacks had an average score that was 37 points lower than whites, about the same gap as was found in 2009.