Data from US Census

Here is a link to all of the data available at Census.gov:
https://www.census.gov/schools/resources/data-tools.html

Here are activities specific to sociology:
https://www.census.gov/schools/activities/sociology.html

Here are teacher suggestions for using Census data:
https://www.census.gov/programs-surveys/sis/about/teachers-guide.html

Data from Pew Research Center

Pew has reports on different subjects including social trends.

http://www.pewresearch.org/