This document discusses the skill of stimulus variation in microteaching. Stimulus variation refers to changing teaching behaviors and stimuli to sustain student attention and understanding. It is important for enhancing active involvement, understanding, liveliness, grabbing attention, minimizing boredom, and motivating students. Effective stimulus variation includes changing position, gestures, speech patterns, focusing, and switching between oral and visual presentation. Topics that benefit from stimulus variation include poems, dialogues, stories, and grammar lessons. Teachers should purposefully vary questions, facilitate discussions, demonstrate physically, use gestures while talking, and interact with students. They should avoid unnecessary movements, standing in one place too long, and playing with teaching materials.