The Science of Wool
Whenever I am working with a new fibre with my students, I get them to think about the science and history that goes with it. Wool holds a myriad of opportunities for
the children to further their scientific explorations.
As well as the lesson below, children can investigate the complex molecular structure of wool (which makes it uniquely suited to absorbing all kinds of dyes) or test its effectiveness as an insulator, or its shrinkage rates. They can also investigate the different breeds of sheep – their origin/ history and the specific traits of the breed that makes them suitable for wool/meat production or adaptations to suit different environments.
In my classroom, we have bags of raw fleece from at least half a dozen different breeds, which the children can look at under the microscope, wash, card and spin, or otherwise investigate so they gain an understanding of the variety of wool available.
Many breeds of sheep have associations that are happy to help teachers (or children) and will likely send you samples of their wool. Raw fleeces can also be purchased online and it is worth telling your supplier that you are a teacher and asking them to throw in a handful of fleece from any other breed they have. Then you can print off a picture and some information about of the breed that the fleece came from and laminate it to attach to a cloth bag/basket of the fleece for your handwork shelf.
Here is one of the introductory wool science lessons from my book: The Work of Wool - A Montessori Handwork Album. It gets children thinking about the properties of wool compared to the fibres of other mammals. It also helps them to understand why felting works.
regular text - what I say
Italic text - what I do
Wool Has Scales Lesson
I would like to show you something that is special about not just wool, which is the hair of a sheep, but also our own hair.
I would like you to take hold of one hair from your head between your finger and thumb and slide them from top to bottom. How does it feel? (Smooth, soft.)
Now try running your fingers back up the other way. How does that feel? (Rough, jerky)
Why do you think that is?
The outside of each of your hairs is covered in overlapping scales. When we smooth them downwards they are smooth and soft, when we rub them up they are rough and prickly.
Have a look at this picture. It is a human hair viewed through a microscope. Can you see all the little scales?
Encourage children to rub the length of their hair both ways a second time with the scales in mind.
We are not the only mammals with scales on our hair. Sheep have them too. Here is a picture of a sheep’s hair – a single strand of wool - viewed through a microscope. Can you see the scales?
Have you ever worn a garment made out of wool and found it a little itchy? That’s because of the scales. Different breeds of sheep have different sized scales on their wool which makes some wool feel itchier than others. This picture is of merino wool which is the finest. It has the smallest scales and is the least itchy.
I have some slides here that have strands of different types of wool on them. You can have a look and see which have large scales and which have small ones.
You might like to sketch them, or do some research about the breeds of sheep they have come from.
Note: if you have trouble finding different raw fibres, ask you knitting community. They will have odd balls of various fibres such as merino, mohair and generic 'wool'. Just pinch a single fibre from a scrap of yarn - it doesn't matter if it has been dyed. Alternatively, you can use the picture below.
I'd love to know how you get on investigating different fibres, please share your findings in the comments sections below, or on the Montessori Handwork Facebook page or the Montessori Handwork Threads Facebook group.