Development of a standardized curriculum and customized test for mathematics is described. Because of the diversity of the New York City school system, a centrally-planned curriculum became a necessity for continuity and quality. The present mathematics curriculum has been in existence since 1982, and is both comprehensive and cyclical. Five strands in mathematics are mandated statewide: (1) numbers and numeration; (2) operations with whole numbers; (3) operations with fractions; (4) probability and statistics; and (5) geometry and measurement. Performance-based objectives are stated in behavioral terms for students at each grade level. A standardized test customized to the curriculum was developed from the shelf form of the Metropolitan Achievement Test, and was first given in 1986. A revised version was developed in 1987. Staff development programs familiarized teachers with the test and its implications for classroom instruction. These workshops, in 1987 and 1988, reminded teachers that they must follow the New York City curriculum for their students to do well. (SLD)