What really has me perplexed is that her teacher's process starts with a 4.5" block instead of a 5" block. I kept thinking the end result was supposed to be 4.5" 4-patches, which - as you pointed out earlier - would require starting with 5" squares.
I'm so left-brained I automatically think in terms of 10 or 12 inch finished blocks. A 7 or 14" block just didn't make it to my mental list of possibilities. I kept trying to figure out how to star with 4.5" squares and end up with 4.5" patches. If it can be done, it takes greater skills with a slide rule than I'll ever have. LOL