The purpose of this activity is for students to use groups of 10 tens to compose multiples of 100. Students use base-ten blocks to make a group of 10 tens and exchange it for 1 hundred. They find the total number of tens and represent the same quantity with hundreds. When students make connections between the number of tens and hundreds they need to represent each number and the digits in the three-digit number, they look for and express regularity in repeated reasoning (MP8).

If you do not have enough base-ten blocks for groups of 4, you can make larger groups of students to use fewer blocks.

• Invite previously identified students to share how they reasoned about ways to represent 300.
• “¿Qué observaron sobre el número de decenas y el número de centenas?” // “What did you notice about the number of tens and the number of hundreds?” (10 tens = 1 hundred, 20 tens = 2 hundreds, 30 tens = 3 hundreds)
• “¿Cuántas centenas tengo si tengo 80 decenas?” // “How many hundreds do I have if I have 80 tens?” (8 hundreds)

The purpose of this activity is for students to make sense of representations of more than 1 hundred. Students recognize that base-ten diagrams can be used to represent hundreds even when all of the ones are not outlined. Students make connections between multiples of 10 and multiples of 100, as they consider the relationship between 70 tens and 7 hundreds. Students describe how grouping tens and counting units of 1 hundred help to count and represent large numbers.

• “¿Cómo saben que se muestra 700 de la manera que Jada lo quería hacer?” // “How do you know that Jada’s way shows 700?” (You could count each hundred block by 1. You could count the squares by 1. If there are 7 hundred blocks, then it shows 700.)
• Invite previously selected identified groups to share how they organized their blocks when using Han’s way.