Even though the Vikings were here first, that knowledge didn't result in understanding what was here or spur growth. If it had then, Europe would have widespread knowledge of America. Columbus' accidental discovery of the continent while trying to get to China proves it.
Later Amerigo Vespucci, explored and wrote widely distributed stories about what later bacame known as America. Which included both North and South Americas.
What I learned in school was a Viking discovery that led to nothing. Columbus discovered it again and that led to others exploring and later settling America. It was a progression. Dropping particular points of history accomplishes nothing.