I was poking around updating the Archaeology Fieldwork for 2009 when I ran across an interesting project from the University of Calgary. They're offering in-school programs, where the archaeologist comes to the classroom (K-6) and teaches archaeology in half-day increments. Take a look:
University of Calgary In-School Programs
Added: I've since discovered other similar programs, including one sent to me via Twitter, so I've put together a page of Archaeology Projects for Kids, including excavations and classroom activities. Please let me know if you know of any others.


Comments
Thanks for listing our summer programs! We also have a bunch of free stuff on our website for teachers including curricula and electronic field trips:
http://www.crowcanyon.org/education/student_resources.asp