Much of the literature on college teaching discusses alternatives to the lecture format. Even if you want to create and teach courses which use discussion, group work, and other student-centered learning activities, writing and presenting an effective lecture is still a useful and necessary skill. Combining short lectures with active learning keeps students engaged as full participants in the class, while still giving the instructor the ability to provide context and information. Some types of courses may necessitate lectures to cover the material, and as you move from graduate student instructor to faculty member, you can expect to be called upon to lecture to undergraduates, regardless of the type of institution at which you teach.
To develop and deliver effective and interesting lectures requires skill. Graduate students, particularly in the humanities and social sciences, tend to become quite adept at writing papers, but they may not realize that a paper doesn’t transfer into a lecture easily, and the kinds of things that may make for a good paper, like analytic detail and a fine-grained argument that engages with the literature in depth, does not make for a good presentation. Inexperienced lecturers may try to cram in all of their knowledge on a given subject, but the purpose of a lecture is not to show how much you know or present your excellent analytic skills; it is to help your students learn, and you can do that best by limiting the number of points you make and the information you provide. Students will retain more if you provide them with less material.
A lecture should have one central topic and a few main points. At the beginning, you should announce the objectives of your lecture—what you will cover, and how you will do so—and explain the significance of what you are trying to convey. In other words, relate the central concept of the lecture to the course as a whole; put the material in context for students. Give students an overview or outline of the lecture up front, or perhaps develop a PowerPoint presentation, to help them follow along. Remember that students are listening, not reading, so they can’t go back and re-visit a confusing sentence or look up a difficult word. Avoid complex sentence construction. Use simple, direct language, and offer aural guides along the way, with expressions like "the second argument against..." At the end, reiterate the main points.
In discussing your main points, try to provide illustrations and memorable examples. Instead of just describing a concept, try to demonstrate or apply that concept to a particular situation. Don’t use the lecture to simply go over the textbook or reading material. If you spend the lecture explaining the readings to the students, they will quickly learn that they need to either do the reading or come to class, but not both. A lecture can and probably should make connections to the text, but instead of recapping it, amplify important points, explain tricky concepts, make connections between the reading and other issues or concepts, or link the reading to real-world examples.
You may be tempted to write down, word for word, what you plan to say in your lecture. This is a bad idea. Prepare an outline, a list of major points, or whatever type of notes you prefer and write down examples that you want to remember. As you gain experience, you will become more comfortable speaking from notes. A script can make you feel secure, but you will probably end up reading to your students instead of talking to them. If you do this, you are guaranteed to lose your students’ attention, and you won’t be able to make eye contact with students or gauge their reactions to the material. You need to look at your students to see whether they are nodding along, looking confused, or worse, falling asleep.
Remember that students’ attention will wander after fifteen or twenty minutes, so you need to find ways to break up the time and switch tasks every so often, instead of trying to lecture straight through an entire class period. Every once in a while stop for a few minutes and give students a chance to ask questions, pose a question to the class, ask students to reflect on the issues you’re discussing and write for a minute or two, or have students break into small groups or pairs to discuss an issue or a problem. An effective way to recapture student attention, illustrate an idea, and engage students with various learning styles is to interject some kind of media into your lecture: show a very short film clip (30 seconds to a minute or two), play a piece of music or an audio clip, or project a picture, image, map or graph that relates to your topic.
In delivering your lecture, think about how you sound to your students. Make sure you are loud enough to be heard, especially in a large room, and enunciate clearly. Modulate your voice by varying your pitch and tone, so that you don’t drone in a monotone. Be sure to speak slowly; nervous people often speed up, and you need to be sure your students can take notes. Probably the most important thing, in terms of delivery, is to show your enthusiasm for the material. If you are excited and interested in the subject, it will help your students be interested in it. If you seem bored by your own lecture, your students most certainly will be. Teaching with enthusiasm can make the difference in whether or not your students become engaged with the subject matter and the class.
Early in your teaching career, it may be helpful to make some notes after each lecture. Write down which examples seemed to work and which fell flat or caused confusion, and make a note of student comments or questions. This can help you prepare for the next time you teach the course and refine future lectures.