Below is a list of free, online and OER textbooks. Feel free to integrate them into your course, or use them to supplement your knowledge of the topic.
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Stand up, Speak out: The Practice and Ethics of Public Speaking – University of Minnesota, 2016.
This is a complete textbook, via the Open Textbook Library. Chapters about “Researching Your Speech,” and “Concluding with Power” encourage students to develop their own public speaking skills. The text also places a strong focus on “ethics in communication.”
Creative Commons License: CC BY NC SA
Exploring Public Speaking – University System of Georgia, 2016.
Complete chapters of this textbook are available for instant download as PDF files. The book aims to cover relevant material for “an introductory, freshmen-level public speaking course.”
Creative Commons License: CC BY NC SA
The Public Speaking Project – The Public Speaking Project, 2011.
Includes by various authors – (Speaking to a Global Audience, Listening Effectively, etc.), that can be downloaded as PDFs. Content varies by chapter and may merit a closer review.
Creative Commons License: CC BY NC ND
Boundless Communications – Lumen Learning
This textbook is viewable online by chapter, and covers many topics under the umbrella of public speaking and communication.
Public Speaking in Context: The ACA Open Knowledge Online Guide – American Communication Association
Chapter 1 is available as a PDF
OER Commons
It’s worth checking out the OER Commons for other ideas – the site is constantly being updated with new resources, assignments, and materials. Here’s a link to a search for Public Speaking – as you will see, there are many resources from all over the country, available for use.