To find the median, we first need to arrange the data in each class in ascending order:
Class 1: 0, 1, 1, 3, 4, 4, 5, 5, 5, 6, 6, 6, 7, 8, 10
Class 2: 0, 0, 1, 2, 2, 2, 3, 3, 4, 5, 6, 6, 7, 9, 10
Since there are 15 students in each class, the median will be the average of the 7th and 8th numbers in each set (or simply the 8th number in the ordered list).
For Class 1, the median number of books read is 5.
For Class 2, the median number of books read is 3.
Therefore, Class 1 has a higher median number of books read during the summer.