Collaborative writing software for Macintosh

[LARRY NIEBUR <lniebur@INS.INFONET.NET>]

I am looking for a Macintosh program that will allow multiple students and
their instructor to edit and "mark up" with proof reading marks a single
composition.  Each student collaborating in the writing will have their own
transparent screen to mark on and make suggestions for editing.

There used to be a program like this called "Markup" from a publisher called
Mainstay, but I cannot contact them anymore.

Will someone suggest a similar program along with a price and source?

TIA!

Larry
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lniebur@ins.infonet.net
Larry Niebur, Coordinator of Computer Services
Northern Trails Area Education Agency
PO Box M
Clear Lake, IA  50428  phone 515-357-6125  fax 515-357-3201
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