(Reuters) - U.S. eighth-graders have improved their performance in science marginally since 2009 and a rise among black and Hispanic students' scores has narrowed racial achievement gaps, according to a report released on Thursday.

In 2011, two-thirds of students performed at or above a "basic" achievement level on the science assessment test, suggesting at least a "partial mastery of the knowledge and skills needed for proficient work," according to the National Assessment of Educational Progress, also known as The Nation's Report Card.

At the same time, 32 percent of students performed at or above "proficient" and 2 percent performed at an "advanced" level, the analysis found.

The test is scored on a scale of 0 to 300, and the average result increased two points between 2009 and 2011.

Hispanic and black students demonstrated a more significant improvement than white students, narrowing but not eliminating the racial achievement gap. Scores of Hispanic students rose by five points, while black students scored three points higher in 2011 compared to 2009.

The gender gap remained unchanged, with male students scoring five points higher on average than female students in 2011.

"The gains are encouraging, but the racial and gender gaps show a cause for concern," said David Driscoll, chairman of the National Assessment Governing Board, a body created by Congress to monitor the quality of U.S. education.

"In order to compete in globally competitive and expanding fields like technology and medicine, we must make sure we give our students the tools necessary to excel in an important subject area," he said.

The assessment also found that students who performed daily hands-on science activities scored higher on average than students who performed them less frequently.

The test results will be used to establish benchmarks to compare the performance of U.S. students, and their global competitiveness, to students in other nations. An analysis comparing the science achievement of U.S. eighth-graders with students from other countries will be released later this year.

The 2011 science assessment test measured knowledge and abilities in physical science, life science, and earth and space sciences.

(Reporting by Edith Honan; Editing by Barbara Goldberg and Jim Loney)