An embodiment of a method of cementing comprises: introducing a cement composition into a subterranean formation, wherein the cement composition comprises cement kiln dust, a natural pozzolan, and water; and allowing the cement composition to set. Another embodiment of a method comprises: introducing a cement composition into a subterranean formation, wherein the cement composition comprises a cement, a natural pozzolan, and water, wherein the cement comprises Portland cement interground with burned shale; and allowing the cement composition to set. Another embodiment includes a cement composition comprising at least one additive selected from the group consisting of cement, cement kiln dust, Portland cement interground with burned shale, and a combination thereof; a natural pozzolan; and water.