The larger difference is what happens after a test is failed and a student is feeling down. It seems that the more affluent group has more "identity formation"

The larger difference is what happens after a test is failed and a student is feeling down. It seems that the more affluent group has more "identity formation" in that they know that they belong at college, whereas the more at risk groups (like students with parents that aren't college educated) sometimes panic, and feel like they don't belong at college, after a mistake of similar size. And that feeling is what causes them to drop out, more than X number of failed tests.