Matthew's statistics class covered chi-square goodness-of-fit tests. In this course, he learned how to use this statistical test to assess whether observed categorical data matches an expected distribution. The curriculum included understanding the chi-square test statistic, calculating expected frequencies, and interpreting results to determine if there's a significant difference between observed and expected values. This statistical technique is valuable for analyzing categorical data and drawing conclusions about the goodness of fit of a model to the observed data.