Okay, something very short, with thanks to Avery Pickford: How do sunflowers organize their seeds? Why is phi the most irrational number? How are these two questions connected, and how can we model that in CODAP?
Here is the YouTube video from Numberphile that inspired it. Worth a watch.
And here is a CODAP document:
https://codap.concord.org/releases/latest/static/dg/en/cert/index.html#shared=149141
A Best-Case Scenario 