Montgomery County schools officials plan to survey students taking high school final exams in math next week about how they think about and prepare for the biggest test of the semester, as school leaders explore the causes of steep failure rates on the countywide tests.

The officials say they still have no clear answers for why a majority of 30,000 high school students in the high-performing district failed their finals in key math courses last year. The low grades came to public attention as data about the tests circulated in the spring, underscoring a problem that had gone on for years.

A work group studying the issue will make recommendations by March, said Erick J. Lang, associate superintendent for curriculum and instructional programs. A report was expected in November, but the issue has not been easy to unravel, he said.

Some parents and educators have suggested that the problem might be that students have been advanced too quickly in math courses or that they lack academic support. Many blame grading policies that leave students assuming that the test will not affect their course grades.

“It’s a very complex issue, and there are lots of different perspectives on it in terms of what people think is the root of the issue,” Lang said, adding that the student survey could be illuminating. “The student voice is an important part of the puzzle,” he said.

School board member Michael A. Durso, who urged such a survey last fall, called the student comments critical. “How are we going to know where we are with this if we don’t get input from the kids?” he asked.

The exam work group has met quietly since July, posting some of its documents on the district’s Web site. A survey of school principals is planned for this month. In the fall, surveys of middle school and high school math teachers were conducted.

Nearly 70 percent of teachers responding to the survey cited at least one of three issues linked to the failure phenomenon, according to documents obtained by The Washington Post.

Teachers said students don’t adequately prepare for exams. They also said some students don’t know how to get ready for such tests, which are cumulative and cover material taught across more than four months.

Grading practices were also cited as a problem. In Montgomery, semester exams are worth 25 percent of a course grade, a significant amount but often not enough to sway a course grade based on two quarters of classroom work.

Many students consult a widely available chart on grading scenarios as they decide how much to study. The chart shows, for example, that a grade of C for each of a semester’s two quarters will go unchanged because of a failed final exam.

“Some kids will only study for exams if they know it makes a big difference for them,” said Amy Watkins, a math teacher at Walter Johnson High School in Bethesda.

Another high school math teacher, who spoke on the condition of anonymity because of the issue’s sensitivity, said the curriculum also is a major problem.

“We teach way too much, way too quickly,” he said. Some students “can learn enough for a quiz in a week, or a unit test in two weeks, but they’re not going to remember it on a final exam three months from now.”

Russell Rushton, who heads the math department at Walt Whitman High School, also in Bethesda, said he was glad that the exam work group was not trying to speed up its efforts in time for January exams. “It’s not going to be an easy solution,” he said. “It’s a multi-faceted problem that they are going to have to take some time to think through and analyze.”

In Montgomery, most students who fail exams still pass their courses.

For June final exams, about 70 percent of high school students failed in Algebra 1 and geometry, for example, but course failure rates were about 20 percent. In honors math classes, exam failure rates were 24 percent to 32 percent, with course failure rates just 2 percent to 4 percent.

Such issues have touched off debate about whether to give final exams more weight toward course grades or make passing the exam a requirement for course credit. Others say final exams should count for less, as they do in many school districts.

As the exam work group continues to meet in Montgomery, all high schools have created action plans to identify and support students struggling in math.

In the spring, educators at Rockville High School conducted their own survey of math students, finding that more than half of almost 600 students studied for math exams one hour or less.

Nearly 57 percent of Rockville High students said they had studied “hard” for their math final, according to a data summary released last year. More than 40 percent of students said they had not studied hard, and half of that group attributed it to already knowing they would not do well.

One teacher, quoted in recent teacher survey results, advised: “Make sure children are properly placed. Give kids a reason to care about their grade.”

Said another, “Make the semester exam really count.”