A choropleth map displays Massachusetts school district boundaries as gray polygons with teal outlines. The visualization uses a topojson data source loaded via `d3.json` and converted to GeoJSON features with `topojson.feature`. React manages the component state while `d3.geoPath` with a `geoIdentity` projection renders the shapes, using `reflectY(true)` to correctly orient the map coordinates. The SVG output is scaled to fit a 960×500 viewport using `projection.fitExtent`.