## What is a subtraction grid?

Subtraction Grids is a mental maths game involving subtraction skills. It has two playing modes, where players need to select either one or two numbers from the grid to complete the subtraction calculation. Each mode has six levels of difficulty and questions are randomised each time the games are played.

## What is a subtraction chart?

A subtraction table is a pattern of arrangement of numbers that helps us to find the difference between numbers by observation.

**What are the parts of subtraction?**

The minuend, subtrahend, and difference are parts of a subtraction problem. In the subtraction problem, 7 – 3 = 4, the number 7 is the minuend, the number 3 is the subtrahend and the number 4 is the difference. Here’s another example of a subtraction problem. 1.

### How to use the 100 chart for addition and subtraction?

Using the 100 chart for addition and subtraction. The next step is to gain fluency with the 100 chart and use it to add or subtract. For addition, the students locate the first number of the expression and add the second one, tens, and ones. Start by adding single-digit numbers, then one ten, more tens, and then two-digit numbers.

### How do you use hundreds charts?

Use hundreds charts for counting, sequencing, pattern building, looking for patterns, and investigating patterns. They’re really great for that, but I just don’t see kids using hundreds charts in a conceptual way that builds great number sense and thinking strategies.

**Is the hundreds chart the wrong model to use?**

So if the students are taking more time, and you’re spending more of your time actually teaching how to use the hundreds chart versus how to add and subtract, then it’s the wrong model. The focus should be on addition and subtraction strategies, not using that particular model.

#### How to teach addition and subtraction of 2-digit numbers?

A smart next step to take in teaching addition or subtraction of 2-digit numbers is to break down a round number into tens. Students rely on their prior learning about counting by tens on the hundred chart to arrive at an answer. Here, they begin with an equation and work it out using the hundred chart: