Sense-making is an essential process in learning for understanding. W e describe a study of sense-making involving two pairs of students learning basic elements of the visual programming language Prograph. The study emphasizes the critical role of activity in mediating concept development and refinement Video protocols of learning behavior were recorded and analyzed. The analysis focuses on the situated nature of the meaning construction process. It reveals how exploration, explanation, and expectation play important roles in the sense-making process.