Utilizing short and relevant multimedia products in class can be very beneficial for effective learning experience. I usually show a course-related short video clip at the beginning of the class (esp. for introductory classes) while the students are still entering the classroom and settle down.
For example, if the day’s topic is about ocean upwelling, I show a BBC video clip about visits of thousands of sharks near a submarine mountain. This would show nice connections among the submarine geologic feature, ocean currents and upwelling at the flank of the submarine mountains, transport of higher nutrient-content deep water to the upper layer, boost of productivity by plankton and subsequent small fish, then ultimately large predator fish, like sharks, attracted by bounty of food. Once students are exposed to this complex yet entertaining content with a audio-visual material, they would perceive the scientific principles more readily. They may get confused by the scientific terms, but they still remember the video. Why sharks flourish around sea mounts.
The optimum length of the video for this purpose is about 5 minutes. If I play a video clip in the middle of the lecture, I make sure I chose a video shorter than 3-4 minutes, otherwise I may lose attention of the class. To minimize the loss time of class, I usually play the video before the class time begins. I need to arrive at the classroom at least 10 minutes early for this. I tell the class that the content of the videos are not for the exam but to supplement what they are learning, because some students may think I use it for the exam.
I can also tell a short story related to the video before I begin a formal lecture. I can ask them a few brief questions. This not only primes the students in an entertaining way, but also it helps to loosen the class atmosphere so I can engage them better during the class. A secondary benefit is that I can get the attention of the class from the beginning.
Perhaps most important reason of doing this extra activity is to motivate the students so they become curious and seek the information further beyond the lecture itself.