Although Ms. Barry was not Samantha’s 6th-grade teacher, she was aware of the curriculum Samantha had had, and had also had Samantha in her homeroom that year. Drawing on this shared history, Ms. Barry continues to hold her pointing gesture toward the Shadow Fractions photograph while looking at Samantha. Sustaining the pointing gesture while referencing the previous year’s curriculum, Ms. Barry’s multimodal utterance keeps present together yesterday’s exhibit experience with last year’s classroom treatment of slope. Nodding, Samantha confirms that she remembers covering the topic of slope in the previous year.
I think this gets very tricky when thinking about 'nodding' as a physical cue to demonstrate understanding. As a teacher, I feel like often times this is not a valid way to demonstrate understanding.