There are quite a few Wizard of Oz novels. The most well-known is the original one by L. Frank Baum, but there have been several sequels and spin-offs written by different authors over the years.
In teaching, the 'gallon man story' is extremely useful. Teachers can use it in a hands - on way. For instance, they can have students create their own 'gallon man' using paper cut - outs of the different units. This not only makes the learning process more interactive but also helps students internalize the relationships between the units. Moreover, when students are having difficulty with volume conversions, the teacher can refer back to the 'gallon man'. Say a student is confused about how many pints are in a gallon. The teacher can use the 'gallon man' to show that there are 4 quarts in a gallon and 2 pints in each quart, so there are 8 pints in a gallon. It serves as a memorable reference point throughout the teaching and learning of volume measurements in the US customary system.
As I'm not familiar with the 'king gallon story', it's difficult to determine its significance. It might be significant in terms of entertainment value if it's a fictional story. Or it could hold cultural or religious importance if it's part of a specific belief system. But without knowing the story, it's all speculation.
I haven't heard of the 'king gallon story' before. It could be a story from a particular region, a family tradition, or even a made - up story for a specific purpose. Without more context, it's hard to tell what it is about.
I'm not sure specifically as there could be various 'gallon man stories'. It might be about a character who is related to gallons in some way, like a man who measures or represents gallons in a unique story for educational purposes, perhaps teaching about volume measurement in gallons.