Many decades of attempts to use science to improve education has produced limited success. Greater success will be achieved through research done within the practice of education. The suggestion is not to simply apply learning science to practice but rather to produce new learning science in real educational settings. The increasing use of technology in schools, from intelligent tutoring systems to mixed-reality games, makes it feasible like never before to engage in systematic experimental investigations of principles of learning and techniques for best supporting it. Systematic investigation is necessary because it is now clear that among the trillions of different ways to support learning, existing science tells us too little about what works best. We present the Knowledge Learning Instruction (KLI) framework to provide guidance on how to do learning research in practice in a way that is driven by data, advances new learning theory and provides a roadmap to better education.