A survey released yesterday found that blacks and Latinos are as likely as whites and Asian Americans to be eager and ambitious students, puncturing one of the assumptions often used to explain the yawning achievement gap separating the races.

Far from being part of racial peer groups that encourage sour, self-defeating attitudes toward school, as some scholars have posited in recent years, black and Hispanic survey respondents were more likely than whites and Asians to report that their friends think it is very important to study hard and get good grades.

"It is typically thought that black students are less likely to display high achievement motivation than other students, but this survey shows that is not the case," said Rob Smith, superintendent of schools in Arlington, one of the school districts that took part in the survey.

The survey of 40,000 suburban middle- and high-schoolers was conducted during the 2000-01 school year by the Minority Student Achievement Network, a national consortium of 15 relatively affluent and racially diverse school districts grappling with strategies for closing the achievement gap, one of the nation's most vexing educational issues.

Among the other school districts to take part in the survey were Shaker Heights, Ohio; Ann Arbor, Mich.; Amherst, Mass.; Montclair, N.J.; White Plains, N.Y.; Berkeley, Calif.; and Evanston, Ill.

Although black and Hispanic students in the 15 districts reported good attitudes toward school, they did not perform nearly as well as did their white and Asian counterparts. Forty percent of the black students and 30 percent of Latinos reported having grade averages of C-plus or below, a level of achievement reported by 13 percent of white students and 14 percent of Asians.

Conversely, the survey found that 48 percent of whites and 47 percent of Asians reported having grade averages of A-minus or higher, which was matched by 14 percent of blacks and 19 percent of Hispanics.

Similar disparities can be found across academic measures and across the country. On SAT college entrance exam scores released earlier this year, whites scored an average 1060 out of a possible 1600, and Asian students averaged 1070. Black students averaged 857, and Latinos averaged 910.

Researchers say some, but not all, of the gap is attributable to socioeconomics, even in the relatively wealthy school districts that took part in the new survey. Far more black and Latino students than whites or Asians reported living in single-parent households. Also, while all students reported parental educational levels well above the national average, whites and Asian respondents reported having better-educated parents than did their black and Latino counterparts.

Much of the recent work on the achievement gap has pointed to "peer culture," teacher or parental expectations and other social dynamics for an answer. But the new survey has left researchers thinking more about improving relationships between students and teachers as a means of closing the gap.

For example, the survey found that white students were almost twice as likely as black students to cite "teacher demands" as a reason to work hard in school. Meanwhile, black students were more likely to respond to "teacher encouragement."

Researchers called that distinction subtle, but important. In one case, "a teacher is asking you to submit," said Ronald F. Ferguson, a Harvard University professor who analyzed the survey results. In the other case, he said, a teacher shows confidence that he believes a student can do the work and "is available to help" -- an approach that some schools in the network now emphasize in teacher training.

The survey also uncovered stark skill differences separating black and Latino students from whites and Asians. Far more black and Latino students than whites or Asians reported "completely understanding" teachers' lessons half the time or less. Also, black and Latino students said they spent as much time as whites or Asians doing homework, but the survey found they were less likely to finish it all the time.

"One way you can read all this stuff is that this has been a big problem at least since the 1950s, and probably a lot longer than that," said Christopher Jencks, a Harvard researcher who several years ago co-edited a widely cited book on the racial achievement gap.

"One explanation comes along after another. Maybe it's oppositional culture. Or segregated schools. It seems to me we run through these explanations the way women's fashions run through skirt lengths without getting much closer to solving the problem."