How to Teach Subtraction to Kids: A Parent's Guide

Teach subtraction gradually — from concrete to abstract. First your child takes objects away from a group and counts what's left. Then they draw and count on fingers or a number line. Only at the end do they write it with symbols. Start within 10, show your child the two meanings of subtraction (taking away and finding the difference), and connect subtraction to addition from day one. The real key is calm, hands-on practice in short daily bursts — not long "lessons."

Below is the order in which to introduce subtraction, step-by-step methods you can use tonight, and the most common pitfalls with simple fixes.

What your child should know, and when

It helps to anchor practice to what school expects. In most early-elementary curricula, children add and subtract within 10 in the first year and within 20 — including crossing ten (like 12 − 5) in the second, before moving toward two-digit work. The subtraction progression published by the Maine Department of Education¹ lays this out clearly and stresses that subtraction is really about the difference between two numbers, reached by counting back or counting on.

For a 5–6-year-old, the goal is confident, object-based subtraction within 10. For a 7-year-old, it's smoothly crossing ten and understanding that subtraction and addition are two sides of the same coin. Don't rush: symbolic notation makes sense only after your child understands subtraction with real things.

The two meanings of subtraction every child needs

This is the most important part of the guide. Subtraction has two senses, and your child needs both:

1. Taking away. "You had 7 sweets and ate 3 — how many are left?" This is closest to intuition and where you start. The child physically removes objects and counts the rest.

2. Difference (comparison). "You have 7 blocks, your brother has 4 — how many more do you have?" Here nothing disappears; we compare two amounts and find the gap between them. As the Maine progression notes, subtraction is the difference (distance) between numbers — and a child can find it by counting back from the larger number or counting on from the smaller one.

Why it matters: a child who only knows "take away" gets stuck on "how many more" problems. Showing both senses builds flexible thinking and smooths the path to multiplication and division later.

Concrete to abstract — the proven sequence (CPA)

The most reliable route to abstract notation runs through three stages: concrete → pictorial → abstract (the CPA approach, rooted in the work of Jerome Bruner). Research on this model in primary maths links the hands-on and visual stages to deeper, more durable understanding — see, for example, this study on the influence of the CPA approach², and a practical overview of CPA in the early years³. In practice:

1. Concrete. Your child subtracts with real objects: buttons, blocks, counters. "Put out 8 blocks. Take 3 away. Count what's left." Hand and eye do work the brain can't yet do with symbols.
2. Pictorial. Swap objects for a drawing: circles with some crossed out, or a number line with a jump to the left. This bridges to abstraction — the child sees the structure without touching objects.
3. Abstract. Only now the notation: 8 − 3 = 5. The symbol has meaning because the child can "see" the picture behind it.

The most common parent mistake is starting at step 3. If a child recites answers without understanding, it falls apart on harder numbers.

Four subtraction strategies that work

Once your child understands the meaning, give them concrete tools:

Counting back. Great for subtracting a small number. For 9 − 2, start at 9 and step back twice — eight, seven. On fingers or a number line.

Counting on. Ideal when the numbers are close, like 8 − 6. Instead of counting back six, the child asks "from 6 to 8 is how much?" and counts up: seven, eight — so 2. This is the "difference" idea in action.

The number line. Subtraction is a jump to the left, addition a jump to the right. A number line makes subtraction visible and organizes thinking, which is why it appears in nearly every curriculum.

Number bonds. The child sees a number as a whole made of parts: 7 is 4 and 3. Once they know a number's "partners," subtraction within 10 becomes instant — and that's the foundation for crossing ten.

Crossing ten (like 12 − 5)

This is where many children stumble — and one of the most-searched difficulties. Don't teach "borrowing" as a mechanical trick. Show decomposition:

1. Say: "First, let's get down to a full ten." From 12, subtract 2 to reach 10.
2. We still have 3 left to subtract (because 5 is 2 and 3).
3. From 10, subtract 3 — that's 7.

Written out: 12 − 5 = 12 − 2 − 3 = 10 − 3 = 7. A child who knows number bonds to 10 does this naturally. That's exactly why it pays to master "partners of ten" first.

Always check subtraction with addition

This is one of the most valuable habits you can build. If 12 − 5 = 7, then 7 + 5 must equal 12. Show your child that addition "undoes" subtraction. As a result:

• the child catches their own mistakes,
• they understand that + and − are inverse operations (the same "number family": 5, 7, 12),
• they solve missing-number problems more easily, like 12 − ☐ = 7.

This is where number bonds shine: one number triangle (12 on top, 5 and 7 below) describes two subtractions and two additions at once.

Common mistakes and how to respond

• Subtracting the wrong way (doing 5 − 12 instead of 12 − 5). Return to concrete: you can't take 12 away from 5 blocks. The sense returns instantly.
• Counting from the wrong number. When counting back, children often include the starting number. A number line and saying "I'm jumping" out loud both help.
• Rushing to symbols. If you see guessing, step back one stage (to pictures or objects). That's not a setback — it's the foundation.
• Pressure and comparison. Discouragement blocks learning more than a missing skill does. Keep it short, calm, and daily.

Practicing subtraction with EduBert

Short daily practice beats rare long sessions — and it's easiest to sustain when a child treats it as play. In EduBert, the world of subtraction is City: children practice subtraction as picture-based tasks, including number bonds (part–whole) and checking answers by adding — the very mechanisms this guide describes. Difficulty rises gradually across ten levels, so a 5-year-old starts with small numbers while an older child works up to crossing ten.

Level 1 of every adventure is free, so you can create a free account and see whether this format suits your child before deciding on premium. If you're just starting with operations, read our companion guide on how to teach addition too — addition and subtraction are best built together.

Frequently asked questions

At what age should a child be able to subtract? Most children subtract confidently within 10 around ages 6–7, then cross ten in second grade. These are rough guides — pace varies, and that's normal. What matters more than age is introducing each stage only after the previous one is secure.

Is finger counting okay? Yes. Fingers are a natural, concrete model of number and a good learning stage. Children drop them once mental strategies become faster. Over time, just add other images too (a number line, number bonds).

How do I explain crossing ten, like 13 − 6? Split it into two steps: first get down to a full ten (13 − 3 = 10), then subtract the rest (10 − 3 = 7). The key is knowing number bonds to 10.

How much should we practice each day? Short and regular wins. A few to a dozen minutes a day as play beats long, infrequent sessions. We cover this in how much daily math practice.

What if my child confuses subtraction with addition? Return to concrete objects and name the action: for subtraction we "take away," for addition we "add on." A number line helps too: back versus forward.

---

Subtraction doesn't have to be stressful — for your child or for you. Start concrete, show both meanings, and practice a little every day. If you'd like your child to train subtraction as a game matched to their level, try City in EduBert — the first level is free.

Sources

1. Subtraction Strategies Progression, Maine Department of Education: maine.gov
2. Study on the influence of the CPA approach, ERIC EJ1265106: files.eric.ed.gov
3. The importance of the CPA approach in the early years, Maths — No Problem: mathsnoproblem.com