How Many Groups of 10?

There are 132 flyers that need to be handed out to Extended Day classes. The flyers need to be organized in stacks of ten to make them easier to hand out. How many stacks of ten will there be? How many flyers will be left over?

When looking at a two digit number, it is easy for students to determine how many tens and ones are in the number. When working with a three-digit number, students have to understand a little more about place value. In working with 100, students first need to understand how many tens are in each group of 100 in order to solve. This can be a little abstract for students at first.

To help them understand how many groups of 10 are in 100, we bring out the place value blocks for a visual. Let's start by representing the number 132 with place value blocks.

It is important for students to understand how many groups of 10 are in 100. By using the place value blocks, students can count the groups of ten easily.

When students understand that 1 group of 100 is equal to 10 groups of 10, they are able to solve these problems easily. Student work may look something like the following:

In the strategy above, the student drew a representation of the place value block model to explain her thinking.

In the strategy above, the student used a modified open number line to keep track of the number of groups of tens and singles.

In the final sample above, the student wrote what she knew about the number of groups of ten in 132. These are just several student samples. There are many more ways students can solve and model their thinking for problems like these.

Place Value

As part of our Calendar Math every morning, we review place value. We review it by creating groups of tens and ones for the amount of days that we have been in school. Place value is a very in-depth concept that students began learning in kindergarten and first grade. In order to fully understand the addition and subtraction strategies we will be starting soon, students should have a complete grasp of the concept of place value.

Simply put, place value is the value of where the digit is in the number. In second grade, we do not venture farther than the hundreds place often. Here is an example of what students should be able to explain:

124

-The number can be written as one hundred twenty-four.

-The number can be written as 100 + 20 + 4

-The 1 is in the hundreds place. This means that there is 1 group of 100 in this number. One group of 100 looks like this:

-The 2 is in the tens place. This means there are 2 groups of 10 in this number. Two groups of 10 looks like this:

-The 4 is in the ones place. This means there are 4 ones in this number. Four ones look like this:

- The entire number 124 can be represented as:

Great Place Value Practice Games:

**My favorite!!** Place Value Golf http://www.toonuniversity.com/flash.asp?err=496&engine=5

Dino Place Value Game http://www.ictgames.com/dinoplacevalue.html

Shark Place Value Game http://www.ictgames.com/sharknumbers.html

Introduction to Place Value Movie:

http://www.linkslearning.org/Kids/1_Math/2_Illustrated_Lessons/3_Place_Value/