Bart wakes up in the morning and realizes he is out of his favorite cereal. On his way to school, it rains and he ends up soaked walking. In the classroom, he realizes he forgot his homework and at lunch his pizza didn't have a lot of cheese, on his way home, he loses his favorite ball. Each time something bad happens, it is followed by something good. But Bart focuses on the bad, until his Mother talks to him at the end and has him look back over his day, teaching him that his perception defined the day.