Bloom's Taxonomy is a multi-tiered model of classifying thinking according to six cognitive levels of complexity. In 1956, eight years after a group of educators from the Convention of the American Psychological Association set out to classify educational goals and objectives, work on the cognitive domain was completed and a handbook commonly referred to as "Bloom's Taxonomy" was published. During the 1990's, a former student of Bloom's, Lorin Anderson, and David Krathwohl led a team of editors which met for the purpose of updating the taxonomy, hoping to add relevance for 21st century students and teachers. Published in 2001, the revision includes several seemingly minor yet actually quite significant changes. See here.
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