MORE THAN HALF of Baltimore's ninth graders failed a statewide minimal competency assessment in mathematics. The test results, designed to compare student achievement in Maryland's school districts, have raised serious concerns among parents and the public.

Why are so many students in Baltimore having trouble with mathematics? What can we do to improve the level of student achievement to ensure our young people have skills and abilities they will need?

Many people here and across America believe that poor mathematics achievements result from lack of attention to basic skills. If we could just make sure students learn their multiplication tables, know how to add and subtract fractions and do the basic functions to balance a check book, we will solve the problem of getting all students -- even those in the back row -- to succeed.

But this line of thinking flies in the face of reality. The basic skills movement, with its emphasis on teaching computation through drill and practice, has dominated mathematics education since the early 1970s and has been more of a stumbling block than a stepping stone to higher achievement. In fact, overemphasis on basic arithmetic is the primary cause of poor student performance in mathematics today and poses a serious threat to the nation's ability to provide workers and citizens who can use mathematics to solve complex problems at home, at work, and in the community.

The United States is the only industrialized nation in the world that teaches arithmetic for eight years. Computation isn't mathematics. We are simply forcing students to learn to add and subtract progressively larger numbers, rather than exposing them to mathematical thinking and problem solving.

Teaching mathematics through arithmetic is like teaching a foreign language through the rules of grammar. To speak a language, students need to be able to use words and language structures to communicate real meanings, not simply follow rules for their own sake.

Our students are taught to manipulate numbers, but they don't know what the numbers mean. A recent Business Week article illustrated this point with an anecdote about a state mathematics assessment in California, which asked sixth graders to compute the height of a horse. Among the students with incorrect answers, one-third said the horse was 16 inches tall. Another third said 64 feet. The children calculated, but they did not think about what the numbers meant. They would not or could not use common mathematical sense to assess their conclusions.

Students need to use logic and mathematical evidence to verify results. They need to develop mathematical reasoning instead of memorization of formulas. And students need to learn to solve problems instead of simply manipulating numbers to find "right" answers.

Research and the practical experience of the nation's mathematics teachers indicate that students who are exposed to complex mathematical problems at earlier ages learn better, are more interested in mathematics and achieve at higher levels than young people who learn mathematics through more traditional rote methods. We must begin to teach algebra and geometry concepts in the elementary schools, encourage students to use calculators as "fast pencils," and we must infuse the classrooms with problems that have meaning to students' lives.

Mathematics teachers need parents to understand that when we ask students to estimate the number of clocks in the school or to use calculators to solve real-world problems, we are not shortchanging students on basic skills. The thinking process required in estimation is a key part of developing higher levels of mathematics thinking that are not only part of algebra and trigonometry, but also of architecture, art and science. The use of calculators allows students to become more adventurous in the problems they solve. For example, students can use calculators to crunch the numbers necessary to determine how much material will be required to build a bridge or a housing development or determine the pounds of beef needed to make the hamburgers served in the school cafeteria. In many circumstances, pencil and paper computation is too cumbersome and time consuming.

In many communities around the nation we have made mathematics education more "user friendly" and have seen significant results in student achievement. There is no reason Baltimore City has to be at the bottom of the pack in mathematics learning. With parents' help, we can move our entire education system closer to developing the mathematical reasoning, problem solving and thinking skills young people need to survive -- and thrive -- in an increasingly complex world.

Iris Carl is president of the National Council of Teachers of Mathematics. Patricia Baltzley is mathematics program developer at Johns Hopkins University's Center for Social Organization of Schools and president of the Maryland Council of Teachers of Mathematics.