Mathematical goals

This lesson unit is intended to help you assess how well students are able to solve real-life mathematical problems. In particular, students will develop their abilities in the following areas:

• Using proportional relationships to solve multistep ratio and percent problems.
• Drawing inferences about a population from a random sample of data.
• Making and stating assumptions based on real-life situations.

Introduction

The lesson unit is structured in the following way:

• Before the lesson, students attempt the Selling Soup task individually. You review their solutions and formulate questions that will help students to improve their work.
• At the start of the lesson, students respond individually to the questions set.
• In groups, students combine their thinking and work together to produce a collaborative solution in the form of a poster.
• In the same small groups, students evaluate and comment on some sample responses. They evaluate these responses and compare them with their own work.
• In a whole-class discussion, students explain and compare solution strategies.
• Finally, students reflect on their work and their learning.

Materials required

• Each student will need a copy of the task sheet, Selling Soup, pages 1 to 4 of Responses to Martha’s Survey, some plain paper to work on, a copy of the How Did You Work? questionnaire, a mini-whiteboard, pen, and an eraser.
• Each small group of students will need a sheet of poster paper, a marker, and copies of the Sample Responses to Discuss.
• Provide calculators for students who choose to use them.
• There is a projector resource to support whole-class discussion.

Time needed

20 minutes before the lesson and a 120-minute lesson (or two 60-minute lessons). Timings are approximate. Exact timings will depend on the needs of your class.