As many as one-third of the nation's 40 million school-age children are at serious risk of failing in school and society, creating "massive, urgent problems" for the nation, leaders of 11 education organizations warned yesterday.

Their coalition, known as the Forum of Educational Organization Leaders, said this potentially huge number of unproductive citizens -- many of them handicapped by drug problems, poverty and criminal behavior -- will drain the economy in welfare and social service costs and seriously hamper the nation's ability to compete internationally.

The group called for federal and state governments to guarantee "an array of necessary educational services" designed to help such youngsters graduate from high school.

Suggestions included pre-kindergarten classes, programs to improve parental involvement, assigning "mentors" to students who have repeatedly failed at school and assuring job or college opportunities to high school graduates who meet certain standards.

"If we are to meet this challenge successfully, the reform of the past five years may pale against the requirements of the next 10," the coalition said in a statement.

The statement is not the first to warn of the pressing danger of huge numbers of failing youngsters, but educators said yesterday that a growing body of evidence has prompted them to push the issue to the front of the national agenda.

"The American people have not accepted this as a major concern," said Mary Hatwood Futrell, president of the National Education Association. "Until it becomes a national priority, we'll plod along as we are today."

The educators pointed to the "radical change" in the nature of students, citing these statistics:

Nearly one-fourth of the nation's children live below the poverty line.

Nearly 60 percent of today's 4-year-olds will live in a single-parent household before turning 18.

The rate of births to U.S. teen-agers is twice that of any other Western nation.

Nearly 40 percent of public school students are minorities.

Delinquency rates among children age 10 to 17 have increased 130 percent since 1960.

Drug use by teen-agers is the highest for any industrialized nation.

The coalition also cautioned that the current education-reform movement may be contributing to the crisis by raising standards without providing extra help for students, which encourages more youngsters to leave school before graduation, the educators said.

"High standards without necessary help . . . will result in the nation's social fabric being so riddled with threads of failure that our incredible experiment called democracy will begin to unravel," the statement said.

Organizations participating in the statement represent teachers, school administrators, superintendents, school boards and principals.