Does the starting course change language scores?

A language department wanted to know how the starting course (101, 102, 103 or 204) affected the language ability scores of fifty-nine students who had reached the 204 level.

Yihuang Wu drew histograms of the score distributions for each ability, speaking, listening, reading and writing, and split each by starting course so the distributions can be compared vertically. Vertical lines mark each group’s median and mean. The post notes that there are too few students in each group to tell the differences clearly.