Buffalo jumps(sometimes called pushkins) were used by several tribes to facilitate the killing of buffalo.
It's amazing how the revisionist history of some recent historians/folks concerning American Indians has developed.
Increasingly, observations and research are attacked because they were/are made by non-Indians. As an example, non-indians such as Lewis & Clark, etc made observations of American Indians. Indeed, Lewis made some of the first observations of the Clatsops, Chinooks, Nez Perce, and Shoshone. A good historian and researcher needs to be able to discern between what is reported as observation and the commentary made in regards to that observation. It also would be helpful if more historians made use of oral histories which are central to many tribes.
Revisionists are trying to remark American Indians into all being paragons of upstanding virtue, but that is off the mark, as is painting all American Indians as bloodthirsty savages. Some tribes did scalp, practice cannibalism, abortion, fratricide, slavery, etc - most did not. And the same can be said for many non-Indian societies - then and now.
Educators such as Deven Mihesuah, etc have made a point of writing about the negative stereotypes of Indians - and then themselves try to re-make the image of Indians with the use of stereotypes. Attempts to question them on these issues can sometimes lead to the fallback position of "I'm an Indian, you're not, so you're not capable of performing a fair and balanced study of issues pertaining to American Indians".
The American history in the 1800's and 1900's was as wrong to portray Indians as wild savages, as is a growing number of folks are wrong to portray Indians as being without faults until the white man arrived.
Oops. Just noted that Deven Mihesuah should be *Devon* Mihesuah.