# Parts and Wholes

## Building Block Towers

Children look for all the combinations of blue and red blocks and stack them to build block towers of 3 to 10. From this activity, children learn how a whole, represented by the block tower can be made of parts, represented by blue blocks and red blocks. This exercise prepares children for learning addition and makes it easier for them to remember the addition and subtraction facts later. It also prepares children to learn combination and permutation in the future.

## Making Number Bonds

Children color and sort 3 to 10 wooden shapes into two groups to match number bonds, which shows how a whole is made of two parts. For example, if a number bond shows that number 5 is made of number 2 and 3, children need to drag 2 wooden pieces to one box and 3 to another box. This activity prepares children for learning addition and subtraction.

# Introduction to Addition

## Addition with Number Rods and Addition with Bead Bars

In these two activities, children look for wooden number rods or bead bars that are the same length as another two put together and make addition number sentence by using the number rods or bead bars. Then they make number sentences by using number chips. These two activities visually introduce the concept of addition as adding two numbers.

# Introduction to Subtraction

## Subtraction with Number Rods and Subtraction with Bead Bars

Children compare two wooden number rods or bead bars that are aligned in two rows to see the difference of the two in length. Then they drag another rod or bead bar to connect to the shorter one of the first two so that the two rows are the same length. Next they use the rods or bead bars to make a number sentence. Finally they make number sentences by using number chips. These activities help children understand that subtraction may mean the difference between two numbers.

# Addition Practices and Strategies

## Addition Strip Board

Children use wooden strips of different lengths to represent addition problems and answers for numbers 1 through 10. Multiple variations of this activity are available. Children may practice the addition problems sequentially (1+1, 1+2, 1+3...) or randomly. They may also be asked to identify all the pairs of wooden strips that add to a certain number from 3 to 10. They visualize the answers of addition problems in terms of the length of wooden strips instead of simply memorizing them as facts.

## Addition Snake Game

Children practice addition by using bead bars to make tens. Children are presented with a “snake” made of many colored bead bars. They are asked to count the beads and replace the bead bars with golden bead bars of 10 and a remainder. Then they count the numbers of 10s (golden bead bars) and 1s to determine the number of beads in the “snake”. There are several variations of this activity. In one variation, the “snake” is already created and in other two variations, children need to either randomly create their “snakes” or build the “snakes” in a way so that the adjacent bead bars add to ten. This activity helps children understand the importance of making 10 in counting and adding to large numbers.

# Subtraction Practices and Strategies

## Subtraction Strip Board

In this activity children use wooden strips of different lengths to represent subtraction problems and answers for numbers 1 through 18. Multiple variations of this activity are available. Children may practice the addition problems sequentially (9-1, 9-2, 9-3...) or randomly. They visualize the answers of subtraction problems in terms of the number of squares instead of simply memorizing them as facts.