Learning goals: Teacher Facing Comprehend the word “ratio” (in written and spoken language) and the notation $a:b$ (in written language) to refer to an association between quantities. Describe (orally and in writing) associations between quantities using the language “For every $a$ of these, there are $b$ of those” and “The ratio of these to those is $a:b$ (or $a$ to $b$).” Full lesson plan (warm-up, activities, synthesis, cool-down prompt) from 6.2 Introducing Ratios, Grade 6.