Modern society demands renewed attention on the competencies required to best equip students for a dynamic and uncertain future. We present exploratory work based on the premise that metacognitive and reflective competencies are essential for this task. Bringing the concepts of metacognition and reflection together into a conceptual model within which we conceived of them as both a set of similar features, and as a spectrum ranging from the unconscious inner-self through to the conscious, external, social self. This model was used to guide exploratory computational analysis of 6,090 instances of reflective writing authored by undergraduate students. We found the conceptual model useful in informing the computational analysis, which in turn showed potential for automating the discovery of metacognitive activity in reflective writing, an approach that holds promise for the generation of formative feedback for students as they work towards developing core 21st century competencies.