This Google Docis a compilation of data sets that are published online. The spreadsheet has everything from cities' CO2 emissions, transcripts of nightly news segments, baseball stadiums, and all public Venmo transactions. This data set could be inspiring for a student whose not sure where to look for data.
IPUMS USA (The Integrated Public Use Microdata Series) collects, preserves and harmonizes U.S. census microdata and provides easy access to this data with enhanced documentation. Data includes decennial censuses from 1790 to 2010 and American Community Surveys (ACS) from 2000 to the present.