Question: In the book “Educated” by Tara Westover, chapter 5, what does *scrap* mean in the following?

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> Tony and Shawn had left the mountain, but they’d left to do what my father had taught them to do: drive semis, weld, scrap.
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Answer: 
It most likely refers to working with scrap metal. This could include collecting scrap metal, collecting items (like cars) to make into scrap metal, or disposing of scrap metal. The aim is usually to make money.
"scrap" can also mean "fight" or "argue", usually implying a not too serious conflict. This **might** mean that the father had taught Tony and Shawn to drive semis, weld, and fight. This is a little more plausible because "scrap" as a verb meaning ."discard" is transitive, and should specify what is being scrapped, and if the meaning is "work with scrap metal" then "scrap" is not a normal verb to use, it is normally a noun or an adjective in that context.

However, the tone seems informal so one cannot be sure that non-standared usage will not be present. Without more context, one can only guess.