My recommendation is to introduce eight-ball into school curricula, but in a specific way. Each kid would be required to keep a log of hours spent practicing on his own time, and there would be no minimum requirement. Some kids could practice zero hours if they had no interest or access to a pool table. At the end of the school year, the entire class would compete in a tournament, and they would compare their results with how many hours they spent practicing. I think that would make real the connection between practice and results, in a way that regular schoolwork and sports do not. That would teach them that winning happens before the game starts.
Yes, I know that schools will never assign eight-ball for homework. But maybe there is some kid-friendly way to teach the same lesson.