Lessons for the QGIS Lessons plugin.
Lesson are grouped by folder. Each folder contains a set of lessons, all of them meant to be distributed together. Individual lessons should be stored as subfolders of the parent set folder.
Type python build.py to run the Python task that generates distributables lessons sets. It will create a zip file for each of the lesson sets. Those can later be installed by the QGIS Lessons plugin using the lessons.installLessonsfromZipFile() method