Introduction Training Videos
Pluralsight has an introductory training course available here: http://www.pluralsight-training.net/microsoft/courses/tableofcontents?courseName=orchard-fundamentals
The first part of the Pluralsight video course is free, and subsequent episodes require a subscription.
Course for beginners interested in developing on Orchard, starting with how to use Orchard from the UI.
Introduction to Orchard 1.5 by Sébastien Ros
A 4-part series by Brent Arias:
Introduction to Orchard 1.4 by Bertrand Le Roy:
Orchard CMS for Absolute Beginners - Free Udemy Course
Orchard CMS for Absolute Beginners by Abhishek Luv
Kris van der Mast made his hands-on lab material available to anyone for free: http://www.krisvandermast.com/downloads.html
Grow Your Website using Orchard by Jason Gaylord
Orchard 1.1: Build,Customize,Extend,Ship by Sébastien Ros
Deconstructing Orchard: Build, Customize, Extend, Ship by Brad Millington