Target>Primary sources?

[Carey Bacon <carey_bacon@SMTPGATE.BLAINE.WEDNET.EDU>]

                      Subject:                              Time:  6:22 AM
  OFFICE MEMO         Target>Primary sources?               Date:  1/6/97

I need clarification about what constitutes a primary source, or at least a
couple of references that do a good job of explaining it.  I'm helping some
middle school students prepare for history day in the state of Washington.
Specifically, is a recent publication of exact journal entries from the
1940's considered primary or secondary?  I'm confused about whether the
source has to be in its original state to be construed as a primary source.