Look at the U.S. Census Bureau's World Population Clock. This clock gives an up to the second estimate of the world population. By how much does the population grow in 1 minute? How many people is that per second? Per week?

Using the U.S. Census Bureau's State and County Quick Facts, find the most recent population estimates for your state and county. How does your county population compare to the number of people the world population grows by each week? Are you surprised by the results?

Look at this graph of Historical Estimates of World Population. In what year did the world population start to suddenly increase? What do you think might be the cause for this?

Optional: Make your own version of this graph using the source data provided by the U.S. Census Bureau. You might try graphing data in different time periods to see the increases and decreases in population more clearly.

How might historical events or the quality of life during different historical periods have influenced population growth? Check the World HyperHistory site or other sources to see what may have influenced population growth.

According to this Population Growth Rate Map, in what areas of the world has the population been growing most rapidly?  Why do you think this is?