Marketing plan templates are developed by people who have achieved success online. They capture the lessons the author has learned along the way and save you the time, cost and effort required to develop your own. Once you have mastered a particular marketing plan approach, you can then expand by refining the template you have used or by adopting another template that might be more suitable for the marketing of a different product or service.
A good plan template is also great for keeping parents informed about their kids' activities as well. While this doesn't apply so much for college courses, it's deeply important for preschool through middle school at the very least. Not only does this give parents a way to know what their children are learning about, but it also gives them a chance to participate as well, such as acting as a field trip chaperon or an assistant for a class event. In the unlikely event that a parent objects with the subject the student is learning, the parent will be able to learn this right away rather than in the middle of the semester.