First choose a city from among approximately 50 large US cities by entering it and choosing from the drop-down list. A grid will be placed on the map covering that city. Then, double click on the grid square with the highest population within it (based on US census block information). The highest-population remaining square will give you 100 points, all the way down to 0 for the one with the smallest population. Try to obtain the most points by successively double-clicking on the highest-populated grid square.

PLEASE NOTE: The actual city limits may only cover a small portion of the grid square – so you may have squares with many people in them however those people are NOT in the city limits of the city you chose, so they don’t count.