Research the census data from 1790 and 2000. Submit a report comparing some of the information contained in the reports. For example, where was the demographic center of the country in each instance? How was ethnicity reported? How is census information used? What strikes you as the most interesting aspects of the reports?
The concept of collecting census data has been around for thousands of years. It was a census that brought Mary and Joseph to Bethlehem when Jesus was born. But it wasn't until the United States declared its independence and became its own country that counts were taken so consistently, or census records so well maintained.
There are many uses for census data, but the primary purpose for the creation of the US Federal Census was for tax and representation reasons1. Congress mandated a decennial population count in order to determine how to tax each state. But the data has found many other helpful uses.
Population changes and migration patterns can be mapped based on census records. I'm sure it wouldn't surprise anyone to hear that New York City has been the most populous urban US city on every census since 1790, but the rest of the list has seen some major differences. In 1790, Philadelphia, Pennsylvania was in second place with 28,522 people, but falls to fifth place in 2000 with one and a half million people! There are cities in the 2000 census that did not exist in 1790, like Dallas, Chicago, Los Angeles and of course, Forney. But ironically, one of the two cities that tied for 10th place in 1790 - Southwark, Pennsylvania - doesn't exist today. What is interesting to research is how historical events affect the population densities of different areas of the United States. After railroads reached the west cost, and the Gold Rush fever brought people out, San Francisco hit the population list in just a few short years and by 1900 was in the top ten. Between 1860 and 1870, several cities in the south dropped off the top 100 cities rankings completely, I'm sure as a direct result of the Civil War.
Although not very accurately, census records have shown ethnic population changes. Not accurately because of the way blacks were counted in the decades since the first census, and the lack of counts for other racial groups at the time.