I think you mean S. America. The Aztecs, Mayans and Incas all understood mathematics, they had agriculture and trade specializations, and astrology. They had a written language and understood the concept of domesticated animals and farming.
There is no evidence that this is true for the North American Indian.
Monks Mound
"Monks Mound is bigger than any of the three great pyramids at Giza outside Cairo. “This is the third or fourth biggest pyramid in the world, in terms of volume,” says archaeologist Tim Pauketat of the University of Illinois at Urbana-Champaign."
The Aztecs and Mayans were in North America (Mexico) the last time I looked. They were preceeded by the Toltecs of Central Mexico, the Olmecs of Caribbean coastal Mexico, and included the Zapotecs and Michtecs near Oaxaca. I have seen many of the impressive structures built by these various peoples. If by North America, you only mean the US, then consider the 50 foot high mound built at St. Louis roughly 1,000 years ago by the Mississippean culture. While perhaps the most famous and highest, there were quite a lot of others. That is why they are also known as the Mound Builders.