#### • Number: Place Value, Operations (+, -, x, ÷)

#### Technical Note:

### Mathematical Language

Block, cube, flat, place value, rod, tens, hundreds, thousands, tens of thousands, hundreds of thousands, millions.

### Using Base Ten Blocks

These relationships are designed to show the multiplicative nature of our base-ten system.

*Base Ten Blocks are designed to help students understand place value. *

This relationship helps students understand that 10 ones is 1 ten, 10 tens is 1 hundred and 10 hundreds is 1 thousand.

Rather than refer to the pieces as 1, 10, 100 and 1000, the terms **unit** (cube), **rod**, **flat** and **cubes **are used. Later, when students move from whole numbers to decimal fractions the values of the pieces may be renamed. If the flat is given a value of 1, then the rod would represent one-tenth or 0.1 and the unit cube would represent one-hundredth or 0.01.

#### Representing Numbers

Students need to be taught to represent numbers using the blocks. Thirty-seven is shown by setting out 3 rods and 7 units.

#### Adding Numbers

Forty-two may be added to 37 by combining the two sets of blocks.

#### Subtracting Numbers

Subtraction involves setting out the correct number of blocks and then removing some.

Fifty-seven take 23 would involve setting out blocks to represent 57 and then taking 23 blocks away. This would leave an answer of 34.

### Typical Classroom Requirements

#### class sets:

Minimum:

500 unit, 50 rods, 50 flats, 4 cubes

Recommended:

1000 units, 100 rods, 100 flats, 6 cubes.