Erick,
You are not the first one to ask this question. I do not think there is a way to print a lesson or export its contents. You can appreciate that some lessons are not straight line like yours.
The only work around I can think of is to provide a resource, perhaps dependent upon completion of the lesson for your students. Or a folder which is always available with all the lesson resources.
Could be a class project. You could assign students to take screen captures (not sure if a copy/paste would work) of specific lesson pages and compile those into a study resource in the wiki or database module.
I would like to have the ability to print the lesson in edit page order. One long screen like an expanded edit view, showing just the
title, content and choices of every page. At least I would have something not very cluttered to print or paste into another external program like Word. This is probably not a high priority on the developer's side of improving Lesson and way above my skills in tweaking code.
Hope this helps,
Chris