This volume contains a collection of the papers presented during the First International ACM-L Workshop, which was held in Tucson, Arizona, on November 8, 2006, during the 25th International Conference on Conceptual Modeling, ER 2006. The workshop focused on enhancing the fundamental understanding of how to model continual learning from past experiences and how to capture knowledge from transitions between system states. Active conceptual modeling is a continual process of describing all aspects of a domain, its activities, and changes from different perspectives based on our knowledge and understanding. Included in this state-of-the-art survey are 11 revised full papers, carefully reviewed and selected from the workshop presentations. Rounded off with 4 invited lectures and an introductory and motivational overview, these papers represent the current thinking in conceptual modeling research.