Topics in order: why number the lessons
Numbers answer “what should I start with today”.
Brains like lists
“Topic 4 of 12” is clearer than a folder of dated files. The student sees progress; you see a skipped hole.
New work does not break old work
You can insert a topic between three and four without resending the archive. Chat always dumps the new file at the bottom.
A block for a group
Open the same program for several students at once. Personal notes stay in each cabinet, not in a group thread.