New Zealand has a shortage of skilled workers in information technology (IT). Skills relating to computer programming (e.g., software engineer, applications programmer, software tester, web developer) all appear on the 2019 Long Term Skill Shortage List published by Immigration New Zealand. In many parts of the world, demand for computing graduates outstrips supply. Consequently, New Zealand cannot rely on filling its requirements from other countries. This means that more teachers will be required to teach the more fundamental concepts in these areas. However, despite widespread recognition of the importance of educating programmers, many secondary school teachers in New Zealand have no programming experience and no formal qualification in computer science. In this project, the authors hoped to better understand and improve teacher-student interaction when learning programming at senior secondary level by exploring the following themes: (1) the nature and quality of feedback delivered by existing teachers of programming; (2) differences in feedback that are due to teacher subject expertise; (3) teacher understanding of what students are struggling with, and what information teachers seek, to provide better feedback; (4) use of secondary sources of feedback, such as automated tools; and (5) how to improve the quality and timeliness of feedback experienced by students. The goal was to build understanding of how teachers and students use feedback on syntax, semantics, and style to improve programming skills. To achieve this, the authors collected baseline data and developed and evaluated interventions that would improve the use of feedback.