Lisa Simpson, This Isn't Your Life

Plot:

Discovering that Marge was once a stellar A+ student whose grades plummeted after being distracted, Lisa fears that she will end up just like her mom unless she pledges to focus solely on academics in an encore episode. When Marge makes a secret deal allowing Lisa to attend her dream school, Lisa learns a lesson in family and altruism. Meanwhile, Bart puts Nelson Muntz in his place and unintentionally claims the title of "School Bully"