A D3.js scatterplot matrix compares SAT scores in math, reading, and writing, along with enrollment, across Manhattan, Bronx, and Brooklyn schools. Each row and column corresponds to one of the four variables, producing twelve scatterplots that reveal correlations and borough-specific clusters, with points colored by borough via a d3.scaleOrdinal. Built with d3.csv, scaleLinear, axisBottom/axisLeft, and an SVG rendering, the matrix is generated by nested loops over the variable pairs. A title and legend clarify the plot.