The report issued by the National Assessment of Educational Progress finds that students of all ages have poor knowledge of how the democratic process works, The Christian Science Monitor reports. Although there was some improvement among fourth graders and Hispanic students, overall, civics scores declined for all levels — and in 12th grade in particular.

In a mix of multiple choice and short answers, the test covers topics such foundations of the US political system, the role of citizens in an American democracy and foreign relations. Of the high school seniors taking the exam, only 24% got scores of “proficient” or better. This is a slight drop over the last time the civics test was administered in 2006. Just 4% scored at an advanced level, while 36% didn’t have even the basic understanding of civics.

“Knowledge of our system of government is not handed down through the gene pool,” said retired Supreme Court Justice Sandra Day O’Connor, speaking at the report’s release. “What these scores tell us is that we’re not doing well enough in educating young people about our government and how it works.”

The NAEP results were most encouraging for 4th graders, whose average score rose by 4 points compared to their 2006 results. Hispanic students also showed improvement since 1998; they improved in fourth, eighth, and twelfth grades. The percentage of Hispanics scoring at proficient or better has gone up from 50% 2006 to 56% in 2010.

The achievement gap still remains. While 37% of white fourth-grade students performed at or above a proficient level, just 12% of black students and 10% of Hispanics scored at a similar level. When looking at the lower end of the achievement curve, the results are even more stark: Only 13% of white students score below basic knowledge, while 38% of blacks and 42% of Hispanics receive similar scores.

“The need to focus on who is getting what learning opportunities is key,” says Joseph Kahne, director of the Civic Engagement Research Group at Mills College in Oakland, Calif. Professor Kahne says his research shows that high-achieving and white students are far more likely to get the “best” civics education – debate opportunities, service learning, simulations – than lower achieving or minority students, despite evidence that such students benefit enormously.