Nellie and Laura both have a crush on Jason, the smart-as-Ben-Franklin new boy in school. Nellie also has another new love--a "talking machine" that records the words of anyone who speaks while the machine's crank is turning. When Nellie sees that Jason would clearly rather spend time with Laura, she hatches one of her standard evil plans. She lures Laura up to her room, where the conversation turns to Laura's love for Jason. While Laura dreamily describes her hoped-for future with the budding scientist, Willie cranks away from behind a dressing screen in the room. The next day at school, Nellie plays Laura's words back to the class. A humiliated Laura runs all the way home and has a little breakdown as she tells Pa what happened. Feeling that Nellie's parents should be made aware of the situation, Pa heads for the mercantile. Upon hearing the story, Nels marches upstairs, belt in hand. Unfortunately, we don't get to witness the beating he administers to his awful daughter. What we do witness is Jason professing his love for Laura the next day in front of the class, and them walking home after school hand in hand.
This episode is sweet, but the character of Jason is too old (about 14-15)for Laura, who in turn is too young (about 10) to be "in love". They probably should have let Laura age another couple of years before attempting this episode!