As the other educator has already said, the pre-Civil War United States saw numerous Reform-oriented movements emerging, trying to enact social change within the country. Temperance, abolition, women's rights, movements to improve education within the country, or to improve the treatment of the mentally ill: all of these causes made marked progress during the period in question.
The two that I will focus on in this answer are abolitionism and women's rights and the degree to which they were actually, as causes, very closely intertwined. The United States, pre-Civil War, was a slaveholding society, a fact which caused much moral indignation among its opponents. People like William Lloyd Garrison viewed slavery as a moral evil (and a blight against the country) as well as a religious evil. They were uncompromising in their advocacy against the institution. Meanwhile, consider that during this same time period there were profound social and political inequalities between men and women in the United States. One of the key turning points in this history was the Seneca Falls Convention in 1848, which tends to mark the beginning of Women's Rights as a political movement.
The thing to keep in mind, however, is that these two movements were actually more closely intertwined than one might at first think. Ultimately, both were based in visions of social and political equality and in an even deeper, moral vision of human equality. Therefore, when you look at the Women's Rights Activists, consider that a great many of them were also on the front lines of Abolition. Likewise, abolitionists such as William Lloyd Garrison and Frederick Douglass were avowed supporters of the women's rights movement.