My sons spelling book asked him to write the Proper nouns in his spelling list. There were 8 lines to write them on. In order to fill out all 8 lines he had to list American, African, Mexican and Canadian. Would this be right?
They can't be right because they are all adjectives. By definition a proper noun has to be a noun, and adjectives don't qualify. The point to remember is that a proper noun is the NAME of a person, place or thing - that is John, Mexico, or The Houses of Parliament.