The Cleveland (Kinsman) branch of Nshei U'Bnos Chabad, the Chabad women's organization. The Rebbe's letters to it date from roughly 1955–1964. See also Agudas Nshei U'Bnos Chabad.
Leadership as merit. The Rebbe encouraged the branch's new leaders to embrace their role as a unique merit and responsibility for strengthening Jewish life (IK 3998), and wrote that supporting Torah study for its own sake brings blessing, physical and spiritual, to all involved (IK 3537).
Women's power. He stressed Jewish women's unique power to bring holiness into their homes and communities (IK 8992), and urged them to actively support education and spiritual growth for all children (IK 8805). Just as on Chanukah we add light each day despite the darkness outside, so should their work keep growing (IK 5959).
Sources: the Rebbe's letters cited above.