Applying Proportional Reasoning
Lead students through the “New-tritional Info” lesson on Mathalicious (available for free!) to introduce students to a real-world application of proportional reasoning. The lesson asks an interesting question: What if fast food restaurants labeled their products with exercise minutes instead of calories? Students will apply proportions to answer the question and explore its implications.
After the initial lesson, ask your students: What are the two major variables that we played with in this lesson? They should be able to tell you that food type and exercise minutes were the major factors. Have students research other fast food products - the ones they eat most often, or the ones that most repulse them! - and apply what they learned about exercise efficiency. Students can also investigate rates of calorie burn in other activities not covered in the original lesson for an extra challenge. Wolfram Alpha is an excellent tool for modeling the proportions used in the lesson, and will help them calculate and visualize the data they find.
As your students investigate other fast food products, have them organize their data in a Google Doc. This will work especially well if students are working in collaborative groups - docs and spreadsheets can easily be shared among group members.
Students can present their findings to the class using Haiku Deck. This tool gets students into the habit of making engaging presentations without relying on simply reading a slide. Students will have to consolidate their information and choose just the right visuals to support their information using Haiku Deck.
As students are giving their presentations, assess their information using a rubric on JumpRope. This online grading platform easily ties assessment to standards, so you can clearly communicate how well your students demonstrated their mastery of concepts. When presentations are finished, conference with each of your students and show them their personal rubric. The feedback will be helpful for everyone to set goals for learning as you move forward in your curriculum.
Key Standards Supported
Ratios And Proportional Relationships
Understand the concept of a ratio and use ratio language to describe a ratio relationship between two quantities. For example, “The ratio of wings to beaks in the bird house at the zoo was 2:1, because for every 2 wings there was 1 beak.” “For every vote candidate A received, candidate C received nearly three votes.”
Understand the concept of a unit rate a/b associated with a ratio a:b with b ≠ 0, and use rate language in the context of a ratio relationship. For example, “This recipe has a ratio of 3 cups of flour to 4 cups of sugar, so there is 3/4 cup of flour for each cup of sugar.” “We paid $75 for 15 hamburgers, which is a rate of $5 per hamburger.”1
Use ratio and rate reasoning to solve real-world and mathematical problems, e.g., by reasoning about tables of equivalent ratios, tape diagrams, double number line diagrams, or equations.
Recognize and represent proportional relationships between quantities.
Use proportional relationships to solve multistep ratio and percent problems. Examples: simple interest, tax, markups and markdowns, gratuities and commissions, fees, percent increase and decrease, percent error.