Why did the us government break its agreement with the dakota

That historic agreement ensured the Sioux could retain portions of five states, but ceded all of their land east of the Missouri River to the U.S. government in exchange for money, agricultural aid and strict rules about any access to Sioux territory by outsiders.

Early public-school curriculum was based on strict Calvinism and concentrated on teaching moral values. ... In the 1800s, Horace Mann of Massachusetts led the common-school movement, which advocated for local property taxes financing public schools. Mann also emphasized positive reinforcement instead of punishment.