In response to Doreen's points-
 
IMA's 4 hour programs for students include a 30 minute introductory
slide lecture outlining the nature and history of the site, the research
issues, recent findings, and field methods and data recording
procedures. Student then spend 2 to 2 and 1/2 hours actually working at
the site under close supervison (no more than 4/1 student/supervisor
ratio).  The students excavate with trowels, point plot artifacts,
screen soil, and write descriptions of what they are doing on specially
designed recording forms.  Staff "error checks" all records as they are
created. The final hour or so includes some hands-on artifact sorting
and cross-mending activity w/ discussion of how the archaeological
record is formed and what archaeologists do with excavated materials.
The final few minutes focus on preservation law and ethics.  The
students are then thanked for having helped preserve a part of the
community's history.
 
John
 
John P. McCarthy, SOPA
Senior Research Archaeologist
Institute for Minnesota Archaeology