In October a family friend, Barbara Giardina (affectionately known as "ya-ya"), came to stay for a week and took the opportunity to help out with some science experiments we had planned to do during school holidays instead of our normal book-work.
We started with trying to build an igloo out of sugar cubes and an icing sugar mix ... well, the icing sugar mix didn't turn out right so we had to keep adding, and adding, till it approached a reasonable consistency. And, whilst the building began well, none of us could quite work out how to achieve an arched dome for the top to finish it. In the end we all walked away in disgust and left our poor friend to battle on!
The object of the exercise was to demonstrate what makes a structure weak or strong, e.g. narrow base as opposed to a broader base, dry packed structures as opposed to those held together by some sort of pinions (dowels or nails) or mortar.