Mathematics · 1st Class · Money · Summer Term

Combining Coins to Make a Total

Learn how to use different coins to make a certain amount of money. We will find all the ways to make 10c using the coins we know.

TL;DR:Turn your pupils into money whizzes with this practical topic on combining coins.

• NCCA Curriculum Specifications
• PSMC: Measures - Money

About This Topic

This topic, 'Combining Coins to Make a Total', is a fundamental component of the Measures strand in the Irish Primary School Mathematics Curriculum (PSMC) for First Class, specifically within the Money substrand. The focus is on moving pupils beyond simple coin recognition to the practical application of combining coins to reach a specific value. This is a crucial step in developing financial literacy and number sense. The activities should be hands-on, using replica euro coins to allow for tactile learning and exploration.

The core mathematical concepts being reinforced here are addition, partitioning of numbers, and problem-solving. By exploring all the different ways to make a total like 10c, pupils are engaging in systematic thinking and reinforcing their addition facts in a meaningful context. This topic lays the groundwork for more complex monetary calculations in later classes, such as calculating change and working with larger denominations, including euro notes. The emphasis should be on discussion and sharing strategies, allowing pupils to see that there can be multiple correct solutions to a problem.

Key Questions

1. Identify two different ways to make 12c.
2. Explain how you can make 20c using only two coins.
3. Compare making 15c with 5c coins versus using a 10c and a 5c coin.

Learning Objectives

• Combine 1c, 2c, 5c, and 10c coins to make totals up to 20c.
• Identify and record at least two different combinations of coins for a given value.
• Solve simple, one-step practical problems involving money.
• Explain their method for combining coins to reach a specific total.
• Compare two different combinations of coins for the same total.

Key Vocabulary

Coin	A round piece of metal used as money.
Cent	The unit of money we use for our coins. It is often written as 'c'.
Value	How much a coin is worth, for example, a 5c coin has a value of five cent.
Total	The final amount you have when you add all the coins together.
Amount	A quantity of money.

Watch Out for These Misconceptions

Common Misconception

A bigger coin is worth more money.

What to Teach Instead

The value of a coin is written on it as a number, not determined by its size. Show pupils a 2c coin and a 5c coin side-by-side and explicitly point out that the 5c coin is smaller but is worth more.

Common Misconception

Counting the number of coins instead of their value.

What to Teach Instead

When a pupil makes 8c with a 5c, 2c, and 1c coin and says they have '3', correct them by modelling 'touch counting'. Touch each coin and say its value aloud ('five, and two more is seven, and one more is eight'), then state the total is 'eight cent'.

Common Misconception

Forgetting the 'c' symbol or the word 'cent'.

What to Teach Instead

Consistently model the correct language and notation yourself when talking about and writing amounts of money. Remind pupils that the 'c' tells us we are talking about money, not just a number.

Active Learning Ideas

Practical Life Work

Classroom Shop

Set up a small 'shop' in the corner of the classroom with items (e.g., rubbers, pencils, small toys) priced up to 20c. Pupils take turns being the shopkeeper and the customer, using replica coins to buy items. This provides a practical and engaging context for combining coins.

25 min·Pairs

Practical Life Work

Coin Purses

Give each pair of pupils a small bag or 'purse' containing a specific set of coins. Call out a total, for example 15c, and challenge them to make that amount using only the coins in their purse. They can then draw their solution on a mini-whiteboard.

15 min·Pairs

Practical Life Work

How Many Ways?

Present a target amount on the board, such as 12c. In small groups, pupils use replica coins to find and record all the different combinations of coins that make this total. They can draw the coins or write the number sentences (e.g., 10c + 2c = 12c).

20 min·Small Groups

Real-World Connections

• Buying a copybook or a pencil in the local shop.
• Saving up coins in a piggy bank for a toy.
• Using coins to buy a treat from a vending machine.
• Paying for a small snack at a school bake sale.
• Finding the right coins to pay for a bus fare.

Assessment Ideas

Quick Check

Observe pupils during the 'Classroom Shop' activity. Use a checklist to note which pupils can correctly combine coins to pay for an item and which need support.

Quick Check

Provide a worksheet with pictures of items and their prices (e.g., an apple for 12c). Pupils must draw the coins needed to buy each item.

Quick Check

Ask pupils to give a 'thumbs up, thumbs in the middle, or thumbs down' to show how confident they feel about making 15c in different ways.

Frequently Asked Questions

Why do we have to find more than one way to make the same amount?

It's a great question! In real life, you might not have the exact coins, so knowing different combinations helps you use the money you do have in your pocket. It also makes you a brilliant maths detective!

What's the difference between a 2c coin and a 5c coin? They look similar.

They can be tricky! The 2c coin is bigger and has a different picture on the back than the 5c coin. Most importantly, one has a '2' on it and one has a '5', so we always need to look for the number to know its value.

Is it better to use fewer coins or more coins to make a total?

Both ways are correct! Sometimes it's quicker to use fewer coins, like one 10c coin instead of ten 1c coins. But both ways still make 10c, which is what matters.