This article describes progress made in organizing US high schools into small learning communities, a practice spurred by the recognition that many of America's large comprehensive high schools had become impersonal and alienating. Small learning community reforms show a pattern of sustained growth over the last four decades but also frequently fail to achieve instructional improvements. The challenge in making instructional improvements is to pursue sound instructional strategies which small scale uniquely positions teachers to carry out, and to make shifts in district policy and practice which currently pose barriers to adopting such strategies.