For this lesson just buy a flowering plant and put it in an odd container like this boot on the right. Emphasize that it is not so important what we look like on the outside but that God's Word and Spirit dwell within us. A good Bible illustration would be 1 Samuel 16. God told Samuel to find a successor for Saul. Among Jesse's sons Samuel was thinking about what each one looked like while God was looking at their hearts. He chose David - a man after God's own heart.
Encourage students to talk about instances where someone or something was not what it appeared to be in their own lives. Talk about how we should seek God's wisdom in our lives.