A student's success in school is highly dependent on the effectiveness of the teacher.  This is not limited to the effectiveness of one particular lesson, but rather the teacher's overall performance in the classroom.  An effective teacher is both compassionate and understanding, while continuing to maintain authority and control in the classroom.  He/She is aware of all the students' individual needs and plans lessons accordingly.  From my experience in elementary school, I would say that the best way to plan an effective lesson is to create a memorable and fun way to get the message across.  The more students are involved in the learning process, the easier it will be for them to internalize concepts and remember that information in the future.  As a teacher, I will use the success of my students as both a motivation and reward for working hard to become the most effective teacher that I can be.