This article examines the educational concepts that were pursued for the benefit of underprivileged children in the era of the New Education Movement. Children's rights in Japanese modernity, as represented by the struggle to apply New Education principles to underprivileged children, are contrasted with the conventional view of childhood in the Japanese tradition. The crucial piece of legal reform that first established children's rights, the Reformatory Law of 1900, is found to derive mostly from a mix of American science and metaphysics based on Japanised Christianity. (Contains 89 footnotes.)