Understand that the two digits of a two-digit number represent amounts of tens and ones. Understand the following as special cases: A. 10 can be thought of as a bundle of ten ones — called a “ten.”

Quarter 1 (Continued throughout the year)

Quarter 2

Quarter 3

Quarter 4

Understand that the two digits of a two-digit number represent amounts of tens and ones. Understand the following as special cases:

a. 10 can be thought of as a bundle of ten ones called a “ten.”

Understand that the two digits of a two-digit number represent amounts of tens and ones. Understand the following as special cases:

a. 10 can be thought of as a bundle of ten ones called a “ten.”

This includes representing 100 with a "flat" base ten block (in quarter 2).

Understand that the two digits of a two-digit number represent amounts of tens and ones. Understand the following as special cases:

a. 10 can be thought of as a bundle of ten ones called a “ten.”

This includes representing 100 with a "flat" base ten block (in quarter 3).

Understand that the two digits of a two-digit number represent amounts of tens and ones. Understand the following as special cases:

a. 10 can be thought of as a bundle of ten ones called a “ten.”

This includes representing 100 with a "flat" base ten block (in quarter 4).

** Continue in quarters 2, 3, and 4 through routines and classroom discussion.

How many different ways can you represent 82 using tens and ones?

Does 4 tens and 8 ones have the same value as 3 tens and 18 ones? Explain your thinking.

Do 2 tens and 6 ones have the same value as 2 ones and 6 tens? Use models and/or hundreds chart to help explain your answer.

A two-digit number has more tens than ones. What could the number be? What is another possibility?

The sum of the digits of a two-digit number is12. Use a hundred chart, what could the number be? What is another possibility?

How are the numbers 30 and 35 alike? How are they different?

Kendra made a two-digit number with a 6 in the ones place. What possible numbers could she have made?

Hundred Chart Spin

About the Math

The concept of ten is a foundational skill in primary mathematics. Students must be able to compose ten in order to add and subtract as well as understand the value of a number. Understanding the composition of a two-digit number is equally important. Students need ample practice so that understanding is intuitive rather than rote or memorized.

There are many different models that can be used to develop the concept. Models for grouping incude: Beans and small paper cups (for groups of 10), Linking cubes, and/or Digi-blocks. Essential vocabulary for this standard includes: place value, digit, one, ten, and hundred(online dictionary, HCPSS Vocabulary Cards).

Pregrouped models include: Base-ten blocks, five and ten-frames, and place value mats.
Virtual base ten blocks , Chip Abacus, and hundred charts are good electronic resources.

The Illustrative Mathematics tasks below demonstrate expectation for this standard.

Rich Tasks for Multiple Means of Expression, Engagement, and Representation (UDL)

1. Have students use base ten blocks, ten frames, digi blocks, and other concrete materials to represent whole numbers. Be sure to stress the connection between the model and place value.

2. Demonstrate how you can set up values in different ways. I can show 3 tens and 6 ones, or 2 tens and 16 ones and still have the same amount of objects. This leads into trading values for addition and subtraction, and exchanging coins while keeping the same value.

3. Ask the students to show 89 in two different ways. I can see that 89 is made of 5 tens, 3 tens, and 9 ones or that is simply 1 one away from 90, or 7 tens and 19 ones, or it is 50 and 39 more. Being able to decompose numbers and building the concept that each representation is indeed the same value aides in efficient and affective mental computation.

Journal Prompt:

How many different "teen" numbers can you show on your double ten frame? Draw a picture and write a number sentence to show how many more than ten each number is.

## Understand that the two digits of a two-digit number represent amounts of tens and ones. Understand the following as special cases: A. 10 can be thought of as a bundle of ten ones — called a “ten.”

## Quarter 1 (Continued throughout the year)

Quarter 2Quarter 3Quarter 4a. 10 can be thought of as a bundle of ten ones

called a “ten.”

a. 10 can be thought of as a bundle of ten ones

called a “ten.”

This includes representing 100 with a "flat" base ten block (in quarter 2).

a. 10 can be thought of as a bundle of ten ones

called a “ten.”

This includes representing 100 with a "flat" base ten block (in quarter 3).

a. 10 can be thought of as a bundle of ten ones

called a “ten.”

This includes representing 100 with a "flat" base ten block (in quarter 4).

## Increasing Rigor

The concept of ten is a foundational skill in primary mathematics. Students must be able to compose ten in order to add and subtract as well as understand the value of a number. Understanding the composition of a two-digit number is equally important. Students need ample practice so that understanding is intuitive rather than rote or memorized.About the MathThere are many different models that can be used to develop the concept. Models for grouping incude: Beans and small paper cups (for groups of 10), Linking cubes, and/or Digi-blocks. Essential vocabulary for this standard includes:

place value, digit, one, ten,andhundred(online dictionary, HCPSS Vocabulary Cards).Pregrouped models include: Base-ten blocks, five and ten-frames, and place value mats.

Virtual base ten blocks , Chip Abacus, and hundred charts are good electronic resources.

The Illustrative Mathematics tasks below demonstrate expectation for this standard.

Rich Tasks for Multiple Means of Expression, Engagement, and Representation (UDL)3. Ask the students to show 89 in two different ways. I can see that 89 is made of 5 tens, 3 tens, and 9 ones or that is simply 1 one away from 90, or 7 tens and 19 ones, or it is 50 and 39 more. Being able to decompose numbers and building the concept that each representation is indeed the same value aides in efficient and affective mental computation.

How many different "teen" numbers can you show on your double ten frame? Draw a picture and write a number sentence to show how many more than ten each number is.Journal Prompt:Print Resources:Math by All Means Place Value 1-2

(56-71)

Brain-Compatible Activities for Mathematics K-1

(23-25)

Mental Math in the Primary Grades

(15-16)

Nimble with Numbers 1-2

(104)

Developing Number Concepts

Place Value, Multiplication, and Division

(34-35)Developing Mathematics with Unifix Cubes

(70-71)

Math Intervention: Building Number Power K-2

(107-110;79-83;46-49)

Web ResourcesGames and CentersLessonsStudent ResourcesVideo SegmentsBase Ten Concentration (2 Digit)Two Digit Numbers with Base 10 Blocks

Printable CentersMy Double Ten-Frame Riddle-Tens and Ones GameMake 10 BundlesTeens on the Ten Frame

Online GamesShark Pool Place Value

Where's My Place?

Wanted: Runaway Number

Sticker Stories

Understanding Tens Rods

Perfect 10's

Lesson SeedsUnderstanding and Using Tens and OnesMystery Number (Game/Lesson Seed)

Teens on the Ten Frame Book Template

Place Value Instructional Ideas

Teacher guide for virtual manipulatives 1.NBT.2

## Questions/Comments:

Contact John SanGiovanni at jsangiovanni@hcpss.org.Use and Sharing of HCPSS Website and Resources:Howard County Public Schools Office of Elementary Mathematics Curricular Projects has licensed this product under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License.