The document discusses stimulus variation, which refers to changing teaching methods and styles to maintain student attention and engagement. It defines stimulus variation as deliberately changing a teacher's attention-getting behaviors. This helps stimulate students and keep them actively participating. The document then outlines various component skills of stimulus variation, including changing movement, gestures, voice, questioning techniques, and incorporating different sensory modes. It emphasizes varying teaching methods like lectures, group work and experiments. The goal of stimulus variation is to avoid boredom through continual changes in instructional approaches.