Adding to 10 · Code with Martin

Plus puts piles together

You have three sweets. Grandma gives you two more. How many do you have now? You put the piles together and count: five. You just added.

Adding is written with the plus sign: +. The writing 3 + 2 = 5 you read: three plus two equals five. It means: three things and two things together are five things.

The result of adding is called the sum. The sum of 3 and 2 is 5.

You meet adding every day, even when it is not called that. Two bricks with five bricks. Three goals in the first half and one in the second. Pocket money from mum and a crown from grandma on top. Each time you ask: how many is that together? And plus answers that.

You can add on fingers, on bricks or by jumping on the number line. All paths lead to the same result. In this lesson you will try them and pick the one that fits you.

Adam and Jonáš are collecting chestnuts. Adam has 4 in his pocket. Jonáš found 3 more under the tree and gives them to him. “How many do you have now?” Adam empties his pocket, adds the new ones and counts everything from the start: one, two… seven. “Seven!” Jonáš shakes his head: “I can do it faster. You already have four. So you just carry on: five, six, seven.” Adam tries Jonáš’s trick with the next chestnuts. It works. And he does not have to empty his pocket every time. By evening they have a full bag and Adam counts each handful out loud: seven… eight, nine, ten. It goes by itself.

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Do not start counting from one. Keep the bigger number in your head and add the smaller one to it: four… five, six, seven.

How to add step by step

I will show you three paths. Example: 4 + 3.

Path 1: piles. Put down 4 bricks. Next to them put 3 bricks. Sweep them together and count them all: 1, 2, 3, 4, 5, 6, 7. The sum is 7. The slowest path, but it always works.

Path 2: counting on. Keep the first number in your head: four. Put up as many fingers as you are adding: three fingers. And carry on counting from four, one number for each finger: five, six, seven. A faster path.

Path 3: jumping on the line. Put your finger on 4. Jump three times to the right: 5, 6, 7. You landed on seven.

One more trick: you can swap the numbers. 2 + 7 is the same as 7 + 2. The result is the same. So always start with the bigger number — adding 2 to seven is faster than adding 7 to two.

The writing is always the same: number, plus, number, equals, sum. 4 + 3 = 7.

5 + 3 = ?

I use counting on.

Bigger number in my head: five. I am adding three, so I put up three fingers.

I count from five, one number for each finger: six, seven, eight. The fingers are used up.

5 + 3 = 8.

Check with piles: five bricks and three bricks, together I count eight. It matches.

2 + 6 = ?

Two is at the front, but it is small. I swap the numbers: 2 + 6 is the same as 6 + 2.

Six in my head. I add two: seven, eight.

2 + 6 = 8.

See the trick? If I added six to two, I would count six jumps. This way only two. Swapping saves work and does not change the result.

7 + 3 = ?

Seven in my head. Three fingers up.

I count: eight, nine, ten.

7 + 3 = 10. I landed exactly on ten!

Remember this. Pairs that make ten together are treasure: 9 + 1, 8 + 2, 7 + 3, 6 + 4, 5 + 5. You will need them in every lesson after this.

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A common mistake when counting on: you say the number you are standing on. 4 + 3 and you count “four, five, six” — you get 6 and it is wrong. The first jump is already five.

Play it

Before you go to the sheet, try it with your eyes. This is not a test — it is a game. Tap until you see it.

Practice: now you do it 🎲

Now try it for real. You will see all the questions at once, like on paper. Start with ten. If it goes well, add more.

Add up to 10. Count on your fingers or jump on the line above.

Practise the questions

On paper

Paper, a pencil and bricks or beans for checking.

Calculate and write: 3 + 4, 6 + 2, 5 + 5, 1 + 8.
For 2 + 7 try swapping: calculate 7 + 2. Did you get the same number?
Write all the pairs of numbers that make 10 together. Start: 9 + 1…
Make up your own adding question about sweets and calculate it.

Now you 💪

I know that plus means put together.
I can count on from the bigger number. I do not have to start from one.
I know at least three pairs of numbers that make 10 together.

✅

Done when: You calculate five adding questions to 10 and a brick check confirms they match.

What to take from this lesson

Plus = put together. The result is the sum.
Start with the bigger number and add the smaller one.
You can swap the numbers in a sum. The result does not change.
Jumping on the line is adding too.
Learn the pairs to ten (7 + 3, 6 + 4…) by heart.