Prior to the start of the lesson, start acting differently than how you normally act. For example, start acting very depressed or very rigid to your students. They will most likely ask what is wrong. Brush them off so that they will compare your current actions to your normal behavior.
Still in character, write compare and contrast on the board. Have students think about their meanings and discuss them with their table groups or partners.
Explain that compare means to find similarities, while contrast means to find differences.
Provide visuals or real-life objects to demonstrate the meaning of compare and contrast.