Jennifer Mack (played by Ally Sheedy) is one of the main characters of WarGames who goes on the adventure to prevent Global Thermonuclear War. Jennifer attends the same school as David Lightman and loves him and even french kissed him.
She’ shown to be indecisive and to change her mind often, as shown when she changed her mind about her biology grade, and when she and David were reserving a flight she changed each of her choices immediately after making them.