Lesson planning is indispensible to research and teaching in American and other English-speaking contexts, and is defined largely in terms of psychological theories of learning and instruction. Popular lesson planning models such as Hunter (1982) and Chatel (2002) make frequent reference to taxonomies and heuristics employing behaviorist, cognitivist and constructivist vocabularies. The most prominent of these heuristics are Benjamin Bloom’s hierarchy of cognitive objectives, and Robert Gagne’s nine “events of instruction.” Bloom’s categorization of educational objectives begins with factual knowledge and ends with synthesis and evaluation, bringing to mind Piagetian and other psychological-developmental hierarchies. Gagne’s sequence of instructional events begins with attentional stimuli and ends with long-term storage and retrieval, bringing together behaviouristic and information-processing lexica. Accordingly, more recent developments in the theory and practice of lesson planning reflect the continuing evolution of normative psychological theories of learning and instruction, including social-constructivist and explicitly eclectic approaches.