North Dakota students once again scored higher than the national average on an achievement test commonly referred to as the nation's report card, though American Indian students were below both the state and national average.

The National Assessment of Educational Progress tests a random sample of fourth- and eighth-grade students in reading and mathematics.

At the eighth-grade level, North Dakota's average math score was 292, compared to the national average of 280. In reading, the state's eighth graders had an average score of 268, compared to the national average of 261.

At the fourth-grade level, North Dakota's average score in math was 245, compared to the national average of 239. In reading, the state's fourth-graders had an average score of 226, compared to the national average of 220.

All of the North Dakota test results except for eighth-grade reading were up from two years ago.

Indian students make up just under 9 percent of the student body in the state's public schools, making them the largest minority group.

In math, the average score for North Dakota Indian fourth-graders was 224 and for eighth-graders 264. In reading, the average score for North Dakota Indian fourth-graders was 204 and for eighth-graders 248.

The average scores for North Dakota Indians were 13-16 points below the national average and 22-31 points below the scores for white North Dakota students.

North Dakota students who qualify for free lunches scored 14-16 points below students whose family incomes are higher.