Estimations and Approximations: The Money Munchers
This lesson unit is intended to help you assess how well students are able to:
- Model a situation.
- Make sensible, realistic assumptions and estimates.
- Use assumptions and estimates to create a chain of reasoning, in order to solve a practical problem.
In this unit, students choose and use mathematics to model a problem situation.
- Before the lesson, students attempt the task The Money Munchers individually. You then review their work and create questions for them to answer in order to improve their solutions.
- At the start of the lesson, students again work individually on The Money Munchers task, answering your questions.
- Next, students work collaboratively in small groups. Their task is to produce a better solution to The Money Munchers than they did individually. Then, working in the same small groups, students analyze responses to The Money Munchers written by students in another class.
- In a whole-class discussion, students compare and evaluate the solution methods they have seen and used.
- In the final part of the lesson, students spend ten minutes reviewing their individual solutions, and writing about what they have learned.
- Each student will need a copy of the task sheet The Money Munchers.
- Each small group of students will need a new copy of the task sheet The Money Munchers, a sheet of poster paper, and a copy of the Sample Student Responses.
- Provide calculators for students who choose to use them.
- There are some projector resources to support whole-class discussion, and to help introduce activities.
Time needed15 minutes before the lesson and a 1-hour lesson. Timings given are approximate and will depend on the needs of your class.
This lesson involves a range of mathematical practices from the standards, with emphasis on:
- MP1: Make sense of problems and persevere in solving them
- MP2: Reason abstractly and quantitatively
- MP3: Construct viable arguments and critique the reasoning of others
- MP4: Model with mathematics
- MP6: Attend to precision
This lesson asks students to select and apply mathematical content from across the grades, including the content standards:
- 7.G: Solve real-life and mathematical problems involving angle measure, area, surface area, and volume.
- estimations_approximations_beta_complete.pdf ( 4203.1K PDF/Acrobat 22 Jun 2012)
- estimations_approximations_slides_beta.ppt ( 1114K MS PowerPoint 22 Jun 2012)
A draft Brief Guide for teachers and administrators (PDF) is now available, and is recommended for anybody using the MAP Classroom Challenges for the first time.
We have assigned lessons to grades based on the Common Core State Standards for Mathematical Content. During this transition period, you should use your judgement as to where they fit in your current course.
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