Drag and drop the base 10 blocks into the white box to make a number (add). To add 7 you can add a 5 block and two 1 blocks. You can click the subtract buttons to remove blocks (subtract). Caution: Once you deposit the blocks you won't see the actual blocks, but see the number in standard form. If you want to use Base 10 blocks on a place value chart try Base 10 Blocks on Place Value Chart.

Suggested Lessons or Activities:

give the students a target to reach (e.g., 3458) and find the fastest way to make this number using the fewest number of moves.

This also works in reverse. The fastest way to subtract blocks until you reach 0.

Drag the white box and place it over the number. Add or subtract blocks and ask the students what the new number should be (Mental Math).

Drag the white box behind a certain block to make the repetitive additions easier (e.g., patterning - counting up by 1, 5, 10, 50, 100, 500, 1000).

Use both the addition and subtraction options to reach a certain number the fastest (e.g., 3999: add 4 thousands and subtract 1).

Model adding strategies. For example, to add 999 and 347 follow these steps: show that 1000= 999+1, 1000+347=1347, and if we subtract 1 from the sum we get the correct answer 1347-1=1346.

Subtraction buttons can be used to demonstrate negative numbers (when in negative range, you will hear a siren).

Students can be asked to record their ideas before they test them out so that they can revisit their steps. The addition and subtraction exercises boost number sense in students (composing and decomposing numbers). This can be used in class (using an IWB), the computer lab, or at home and with any Flash enabled Tablet.

## Base 10 Blocks for Modelling Numbers and Addition and Subtraction

## Modelling Whole Numbers and Addition and Subtraction

© R. Mirshahi

## Modelling Decimal Numbers and Addition and Subtraction of Decimals

Base 10 blocks can be used to model decimals as well. In the following resource we have used a flat and let it represent 1.© R. Mirshahi

## Instructions:

## Suggested Lessons or Activities:

- give the students a target to reach (e.g., 3458) and find the fastest way to make this number using the fewest number of moves.
- This also works in reverse. The fastest way to subtract blocks until you reach 0.
- Drag the white box and place it over the number. Add or subtract blocks and ask the students what the new number should be (Mental Math).
- Drag the white box behind a certain block to make the repetitive additions easier (e.g., patterning - counting up by 1, 5, 10, 50, 100, 500, 1000).
- Use both the addition and subtraction options to reach a certain number the fastest (e.g., 3999: add 4 thousands and subtract 1).
- Model adding strategies. For example, to
- Subtraction buttons can be used to demonstrate negative numbers (when in negative range, you will hear a siren).

Students can be asked to record their ideas before they test them out so that they can revisit their steps. The addition and subtraction exercises boost number sense in students (composing and decomposing numbers).add 999 and 347follow these steps: show that1000= 999+1,1000+347=1347, and if we subtract 1 from the sum we get the correct answer1347-1=1346.This can be used in class (using an IWB), the computer lab, or at home and with any Flash enabled Tablet.

## Special Features:

## Other Related Modules and Useful Links: