## Chapter 16

### Part 1: Home and School Investigation

Send the Letter to Family (PDF file) home with each child. Collect all of the responses to the survey question and put them in a paper bag. Set up a graph or tally chart on the chalkboard or on a flip chart to record the results of the survey. As the children watch, have volunteers pull a paper out of the bag. Record the ice cream choice on the graph or tally chart.

When you have recorded all the choices, ask questions such as the following:

**How many more people liked chocolate than vanilla?****What is the difference between the number of people who chose chocolate and the number of people who chose vanilla?**

Write the number sentence needed to answer each question.

A good time to do this activity is after Lesson 3 on subtracting from 12 or less.

### Part 2: Be an Investigator

A good time to do this investigation is after Lesson 3 on subtracting from 12 or less.

#### Materials

- Investigator Worksheet (PDF file) for each child

#### Introducing the Investigation

Show the children the Investigator Worksheet. Say, **Write your name and age, and the names and ages of three children not in your grade level, on the worksheet.** Then you will write a subtraction sentence that shows the difference in age between two of the children. Also, write the two children's names that go with each subtraction sentence. Do this as many ways as you can for each name on the worksheet.

#### Doing the Investigation

Observe the children and give them help as needed. Make sure they write the two names that go with each subtraction sentence.

When the children are finished, ask them how many different ways they found. If there are four children, there are six different ways to pair the children to find the differences in age. Give the children more time if they did not find all the ways.