This article examined how mentor teachers help interns in learning to plan lessons.The author revealed that some of the interns attempted to teach meaningful content but failed to consider ahead of time the nitty-gritty details or they attempted to teach a lesson that lacked a clear, worthwhile purpose. She understood that the interns often taught from plans that their collaborating teacher had read through and approved of Hence, she wanted to help the collaborating teachers consider playing a larger role in helping interns strengthen individual lesson plans before interns actually taught from those plans.The author concludes that becoming a teacher of planning requires mentors to possess conceptual and practical knowledge of instructional planning, how novices learn to plan, and how to teach planning.