A Young Man's Fancy - S1.E16

Pearl goes to Baltimore to visit her sister and the Jenkins watch Calvin for her. When he tries out for the romantic lead for a school play and doesn't get it, he becomes depressed. Sandra boosts his confidence and makes him feel better, however, he mistakes her kindness for affection and begins to fall in love with Sandra. When Brenda hears how silly Calvin is acting over Sandra, she goes and talks to him and expresses to him that she cares for him more than Sandra would ever, and she tells him that he is her best friend. Calvin gets over his crush really fast after that.