We have many students and faculty who are requesting the ability to print all the pages in Lessons at once instead of having to print each page individually. They're accustomed to that functionality from the old Melete (i.e. Modules) tool.
My first thought when these requests started to come in was that the Lessons tool's ability to create complex navigation structures makes it too difficult to determine an order of pages for printing. But after looking into a little more, I think the "Index of Pages" provides a manageable place to start.
I've attached a quick-and-dirty Greasemonkey/Tampermonkey userscript prototype that adds a "Print All Pages" button to the "Index of Pages" page and walks through the links on that page and pops them up in one new page for printing all of them. (You may need to tweak the @include/@match lines in the script to match your Sakai instance, of course.) If a page is shared in multiple places in the hierarchy it will print multiple times, but I think that is the best way to represent the structure of the course materials. Naturally it would be better to have Lessons create this pop-up page natively instead of compiling it with a jQuery kludge.