To strengthen their efforts, principal preparation programs should consider training their students to meet clear standards for principal performance, tailoring curricula to district needs and responding to feedback from alumni. That’s the guidance in a report from the New York City Leadership Academy, which has trained numerous principals now leading New York City public schools — and helped prepare many other school leaders in districts around the country. The report offers an in-depth look at the approach to training taken by the leadership academy and offers recommendations on how others can replicate its successes.