Mean vs. Median
The mean is the arithmetic average of a group of scores. The mean is sensitive to extreme scores when population samples are small.
The median is the middle score in a list of scores; it is the point at which half the scores are above and half the scores are below.
Current reports emphasize them equally. Medians are less sensitive to extreme scores and are probably a better indicator generally of where the middle of the class is achieving, especially for smaller sample sizes. Means are the arithmetic average and are often used with larger sample sizes.