## Chapter 7

### Part 1: Home and School Investigation

Send the Letter to Family (PDF file) home with each child. As the children are bringing in their boxes and tracings, check to make sure the boxes and tracings are labeled with their names. Take one of the boxes and the tracing that goes with it. Find another tracing that could not possibly have come from that box. Hold the box and the two tracings for the children to see. Tell them the name of the child who brought in the box, but do not identify the tracings. Ask, **Which tracing do you think was made from this box?** Allow time for children to make their predictions. Then have a volunteer demonstrate how the box was positioned in order to make the tracing.

A good time to do this activity is after Lesson 6 on identifying faces of a solid shape. Do a few of these each day.

### Part 2: Be an Investigator

A good time to do this investigation is after Lesson 2 on plane shapes.

#### Materials

- Investigator Worksheet (PDF file)
- crayons

#### Introducing the Investigation

Hold up the Investigator Worksheet. Say, **We are going to do an activity where we color this group of squares so that no squares that touch are the same color.** Demonstrate this by coloring two squares that are side-by-side with the same color, and point out that this is an example of what children do not want. Then color two squares that are side-by-side using two different colors. Point out that this is an example of what children do want. Point to the squares and say, **These squares touch and are different colors.** Tell children you want them to color the squares so that no squares that touch are the same color **and** you want them to do this using the fewest number of colors.

Put children in pairs to work on this activity.

#### Doing the Investigation

As you watch children doing the activity, ask questions such as, **Are there any squares that touch that are the same color?** This will help children remember the rules.

When children are finished, ask them what they found. Children may have found a way to do it with three or more colors. If so, ask questions such as, **Did anyone find a way to do it with fewer than four colors?** Keep asking until you get an example with two colors. Give additional time to those children who did not have it done with two colors.

Have children share their designs with each other when they are finished. Ask them to talk about what is different about each of the designs and what is the same about each of the designs. Discuss how children used **different** colors in their designs, however, the colors alternate in the **same** way in each of the designs.