CKMath Unit 2: Introducing Ratios
Focus:
Work with ratios extends students’ prior knowledge about numbers and operations. This unit draws on abilities to understand, represent, and solve arithmetic problems involving quantities with the same units. Students learn that a ratio is an association between two quantities, e.g., “1 teaspoon of drink mix to 2 cups of water.” Students analyze contexts that are often represented in terms of ratios, such as recipes, mixtures of paint colors, constant speed (an association of time measurements with distance measurements), and uniform pricing (an association of item amounts with price).
This unit introduces discrete diagrams and double number line diagrams, representations that students use to support thinking about equivalent ratios before their work with tables of equivalent ratios. Throughout this unit, they discuss their mathematical ideas and respond to the ideas of others. In the next unit, Grade 6 Unit 3: Unit Rates and Percentages, students will extend learning from this unit to understand the term unit rate and that if two ratios a : b and c : d are equivalent, then the unit rates are equal.
Number of Lessons: 17
Instruction Time:
Approximately 50 minutes
(Please note that each lesson is designed for one instructional block, and may be divided into shorter or longer segments based on teacher pacing and student needs.)
