# Sampling and Estimating: How Many Jellybeans

## Mathematical goals

This lesson unit is intended to help you assess how well students are able to:

• Model a situation mathematically, justifying any assumptions made.
• Estimate unknown values/missing information when solving a problem.
• Calculate volumes of three-dimensional objects.
• Use an appropriate sampling method to draw conclusions about a population.

## Introduction

• Before the lesson, students attempt the Jellybeans task individually. You then assess their responses and formulate questions that will prompt students to review their work.
• At the start of the lesson, students think individually about their responses to the questions set.
• Next, students work in small groups to combine their thinking and work together to produce a collaborative solution to the Jellybeans task, in the form of a poster.
• In the same small groups, students evaluate and comment on sample responses, identifying the strengths and weaknesses in each approach and comparing them with their own work.
• In a whole-class discussion students compare and evaluate the methods they have seen and used.
• In a follow-up lesson, students reflect on their work and what they have learned.

## Materials required

• Each student will need a copy the assessment task: Jellybeans (printed in color, if possible), a copy of the questionnaire How Did You Work? and some plain paper to work on.

Calculators should be made available on request.

• Each small group will need a large sheet of paper and copies of Sample Responses to Discuss.
• There is a projector resource to support whole-class discussions.

## Time needed

20 minutes before the lesson for the assessment task, a 100-minute lesson (or split into two shorter lessons), and 15 minutes in a follow-up lesson (or for homework). Timings given are only approximate. Exact timings will depend on the needs of the class.

## Mathematical Practices

This lesson involves a range of mathematical practices from the standards, with emphasis on:

## Mathematical Content Standards

This lesson asks students to select and apply mathematical content from across the grades, including the content standards: