I think the idea here is that ABC CBV(Activity Before Concept Concept Before Vocabulary) is valued by the curriculum team at code.org.
So students should do the activity before worrying about the vocab. That said, many of the lessons do have the vocab on the lesson overview page and this one does not. I think that the online lesson have the vocab on the overview page and the offline lessons do not. It seems intentional but I'll pass it along to the curriculum team. thanks.