Here are some recommendations from the workshop participants, listed with the recommender in parentheses:
 
 

Empowerment Evaluation: Knowledge and Tools for Self-Assessment and Accountability.
David M. Fetterman, Shakeh J. Kaftarian, Abraham Wandersman Editors. Sage Publications. 1996. ISBN 0-7619-0024-1
(paperback available – Eve Kedar)

Enhancing Thinking through Cooperative Learning.
Neil Davidson, Toni Worsham Editors. Teachers College Press. 1992. ISBN 0-8077-3158-7
(Eve Kedar)

Information Design.
Robert Jacobson Editor. The MIT Press. 1999. ISBN 0-262-10069-X
(Brilliant book about designing information so that it can be understood and exists within the context of the learners, users. "design of understanding". – Eve Kedar)

Self-Efficacy: The Exercise of Control.
Albert Bandura. W.H. Freeman and Company. 1997 ISBN 0-7167-2850-8
(I have the paperback edition, there is also a hardcover available. – Eve Kedar)