This means the height of the fabric was the width/4 x 1,73.
(Usually crafters will just make the width 4 times the height because math is scary and also because that can be nicely done with pre cut fat quarters, but that will not give a true pyramid: its top will not be in the middle of the ground plane. There’s a Dutch explanation on this Belgian blog.)
I chose the outer fabric to be nice and precise, both in print and in sewed lines to keep the batting inplace. Nice and precise, just like Matilda and my swappee are. (And like I am). My swappee is Meilindis from Meilindis.nl (English blog).
The zipper gives a hint to what else is important:
It’s one of The Woolly Dodo stitchmarkers, without the ring.
This is the inside: chocolate cakes! Like the one the head of the school makes one of the pupils eat in totality. Enjoy some of the marvelous illustrations by Quentin Blake here 🙂