https://www.khanacademy.org/science/hs-chemistry/x2613d8165d88df5e:teacher-resources/x2613d8165d88df5e:unit-guides/a/how-to-use-our-ngss-aligned-unit-guides 2026-03-31T02:36:22.192752012Z How to use our NGSS-aligned unit guides Explore what’s included in Khan Academy's unit guides and how they can support your teaching. article https://www.khanacademy.org/science/teacher-resources-ngss-science-domain/x2811526c37de0eab:unit-guides/x2811526c37de0eab:middle-school-chemistry-unit-guides/a/middle-school-chemistry-unit-guides 2026-03-11T01:40:33.014543209Z Middle school chemistry unit guides You're in the right place for Khan Academy’s science teacher resources—designed to support and empower your teaching! article