As scientific models of student thinking, learning progressions (LPs) have been evaluated in terms of one important, but limited, criterion: fit to empirical data. We argue that LPs are not empirically adequate, largely because they rely on problematic assumptions of theory-like coherence in students' thinking. Through an empirical investigation…

When grading students' quizzes and exams, I find that students are seemingly always changing their answers from the right answer to the wrong answer. In fact, I have cautioned students against changing their answer. Colleagues have made similar observations and some books on test-taking strategies advise against answer-changing. In an effort to…