This monograph provides an overview of the characteristics, attributes, and behaviors that define and identify elementary school students who are at risk of not succeeding in mathematics. The monograph is divided into seven sections that report research to support early intervention procedures to prevent problems from developing and suggest programs, practices, and materials to prevent or reduce problems. Section I, the introduction, identifies two groups of students to whom these programs would apply: the "typical" potential dropout or underachiever and the "nominal" mathematics student who reaches inadequate levels of mathematics achievement to allow him or her maximum educational and life choices. Section II describes some of the variables related to problems of at-risk students in mathematics. Sections III-V describe practices and programs that prevent or reduce at-risk problems related to mathematics achievement from three perspectives: the impact made by schools or organizations; the impact made in the classroom; and the impact made by instructional materials. Section VI describes changes that can be made by schools and individuals in response to the evaluation of present practice. Actions suggested include school restructuring; curriculum modifications; and changes in instructional programs, instructional materials, support services, and parental and community involvement. Section VII provides a list of selected organizational resources to contact for information related to at-risk students. (Contains over 70 references.) (MDH)