But ounces? Color the boys slightly confused. The train of thought goes like this: There are 16 ounces in a pound. A cup has 8 ounces. That means a cup weighs half a pound. Except it might not ~ fluid ounces and ounces as a measurement of weight are not the same thing.
8 fluid ounces of water will weigh 8 ounces, as will other liquids of the same density. 8 fluid ounces of honey weighs 12 ounces. Honey is sold by weight most of the time; I learned a long time ago that 24 ounces of honey by weight will fit into a container that holds 16 fluid ounces.
The word ounce comes from uncia, meaning 1/12, as an ounce was 1/12 of a Roman pound. But an ounce is only 1/16 of avoirdupois pound, which is the pound we use in the United States customary system.
I can't think of any way to teach this other than rote memorization. I didn't come up with a clever story and didn't find one in the various Waldorf materials I have.
Continuing Practice: Subtraction with Regrouping
Concepts Awakened: Adjectives
Main Lesson: Measurement
Afternoon Lesson: Gardening
Other Subjects: Social Studies (A History of US)