A primary source is a source of information that was created at the time under study
A secondary source is a source of info that was created later by someone who did not experience firsthand or participate in events at the time under study.
Primary/Secondary Source Graphical OrganizersThis is one I made for my son:
Included in this printable is a list of types of sources that students can use to fill out the graphic organizer.
Set of 4 Primary/Secondary Resources worksheets with Answer key - These are nice because they give specific examples of sources and students must determine if they are primary or secondary. From CommonCoreSheets.com.