To write
TODO: The opening.
▦Activity
An activity and two check questions, the shape Parts 1 and 2 use. The idea for this part is cleaning one column start to finish, so a fix that quietly drops rows is something the student feels before the notebook asks for one.
▤Lesson
The teaching content for this part goes here, between getting a feel for the idea and doing it for real. What form it takes is still open. A recorded walkthrough, written explanation on this page, worked examples the student modifies, or nothing beyond the job statement and an empty notebook.
To write
The job statement for this part, the way Parts 1 and 2 state theirs.
⌘Notebook
The notebook for this part, opening in Colab the way Part 2's does. It starts from the raw file, so this part works whatever happened in your Part 2 notebook.
▶Video
The practitioner. A messy column and a derived column from real work. What they did, and who they had to ask.
To write
The two comparisons the student makes against the recording, chosen for this part.