 So the document itself needs to contain some general information about the class. For example, the name of the teacher, the date and time of the lesson, what level of class is being taught, and in what room. How many students are we expecting? This is important when we've got things like photocopying and materials to do. What is the context of the lesson? In other words, what is the lesson actually about? What vocabulary or grammar point is this lesson covering? And sometimes it's also useful to write out what the focus of the lesson is. So in effect, the context of the lesson is telling us the grammar point. For example, that might be the present continuous tense, whereas the focus is telling us how we're going to go about teaching it. Another example to illustrate this, let's imagine that we were teaching a starter class about color, then our focus could be the way in which we're going to teach them about color. So we could be using clothes or we could be using fruits and vegetables. So here the context would be color and the focus would be fruit, vegetables, clothes or whatever.