Differentiation is adapting teaching methods and content to meet the needs of individual students. It is based on the idea that students learn in different ways and at different paces. The document discusses the theoretical origins of differentiation in the work of Vygotsky and Gardner. It explains that differentiation is important because all students can learn more when taught appropriately. However, some critics argue that differentiation is just good teaching and that the focus on learning styles is misguided. The document provides examples of differentiation strategies and homework options for teachers.