Pamela is trying to determine if the after-school tutoring program helps improve student test scores. She compares two classes test scores. None of the students in Class A participate in the program. All students in Class B participate in the after school program. The test scores for each class are below. What is the difference in the median scores of the two classes?

Class A: 60, 50, 68, 55, 65, 70, 84, 77, 78, 88, 95, 80, 40

Class B: 59, 81, 60, 68, 67, 50, 74, 92, 80, 95, 91, 78, 58