The Cheyenne Mountain Schools, a small suburban school district in Colorado Springs, Colorado, used the National Assessment of Educational Progress (NAEP) data to compare the mathematics achievement of its nine-year-old pupils with pupils of the same age living in similar communities across the United States. Working closely with NAEP personnel, school district representatives chose 65 NAEP exercises to be used in the assessment. District personnel reprinted the exercises, duplicated the NAEP audio tapes of test instructions, and relicated NAEP scoring and tabulation materials. A volunteer group of 12 mothers from the district hand-scored and tabulated the results. The resulting data were compared to NAEP data for nine-year-olds from communities classified as "high metro," large urban areas where a high proportion of adults are in professional or managerial positions. Among nine-year-olds in the Cheyenne Mountain Schools: (1) Boys performed significantly higher than their national counterparts on 13 of the 65 NAEP exercises, and significantly lower on 13; (2) girls performed significantly higher on 16 items, and significantly lower on 21; and (3) the combined performance of boys and girls was significantly higher on 14 exercises, and significantly lower on 15. (Author/MV) Aspect of National Assessment (NAEP) dealt with in this document: Procedures (Replication).