I received an email the Saskatoon Public School Division that they have released their first open textbook for Computer Science 20. It’s in the form of a website and  carries a CC-BY-SA license.

http://opensask.ca/

Heather M. Ross (B.A., B.Ed., M.Ed.)
Educational Developer (Digital Pedagogies)
Gwenna Moss Centre for Teaching and Learning

Research Fellow
Open Education Group

Room 50.5, Murray Building
University of Saskatchewan
Tel: 306.966.5327
email: heather.ross@usask.ca
http://teaching.usask.ca/index.php

Find open textbooks and other open educational resources on:
http://open.usask.ca