Two combined design cases examine historically significant projects in technology-assisted instruction developed at Stanford in the 1960's and 1970's: Computer Assisted Instruction (CAI) for elementary school students, and the Nicaraguan Radio Mathematics Project (NRMP). The combination of the cases allows for the exploration of the commonalities in instructional design, use of technology, and methodology of each project, and reveals the practical and theoretical forces which positioned the highly experimental CAI as the genesis of NRMP, which became the model for Interactive Radio Instruction (IRI) which itself fulfilled the initial projects' vision of active learning at scale. Today, as we pursue these same goals of student engagement and global access, these two integrated cases offer the successes and failures of the early experiments as considerations for our present designs while establishing a clearer intellectual heritage of technology-enhanced instruction.