They made teepees because they were nomads. (a nomad is a member of a people having no permanent abode, and who travel from place to place to find fresh pasture for their livestock.) Teepees were easy to set up and put away for traveling purposes. Teepees were made out of stretching buffalo skin over a skeleton of 20-30 wooden poles, all slanted towards a central point and tied together near the top. A flap at the top allowed smoke to escape, and a flap at the bottom served as a doorway.
To get to better land to farm I think! I hope this helps!
