Hello Kenji,
If you configure Moodle in order to display blocks in the module pages, you'll
see that you can add a web link to your Lesson:
Site administration -> Appearence -> Themes -> Theme settings ->
In the right side of the screen, activate the option "Show blocks on
module pages".
(this path is for Moodle 1.9-3+, in other versions it may vary)
With this feature on, you can add an HTML block, with a link to a PDF file
with all the content of your "Lesson Book" (if this term is allowed
).
If you insert a small icon of a printer and you add the web link to it, you'll
almost have the same effect that in the Book module.
Well, just an idea ...