6 Mental Math Strategies | Tips and Tricks for Students

Swarnali Saha

Founder, Welcome2Maths | 15+ years as a Math Teacher & Life Skills Coach

Hi there, young math explorers and parents! 👋
I’m so glad you stopped by — today, I want to share something super useful for every student who wants to become faster, sharper, and more confident with numbers: Mental Math Strategies.

Whether you’re a primary student learning your basics, or a middle grader preparing for tougher challenges, mental math is your best friend. And don’t worry, I’m here to break it down in the simplest way possible!

Let’s dive into 6 effective Mental Math Strategies I teach my students at Welcome2Maths.

1️⃣ Break It Down (The Split Strategy)

Big numbers can look scary — but if you split them, they’re much easier to handle!

For example:
48 + 35
Break them into parts:
(40 + 30) + (8 + 5) = 70 + 13 = 83

This method helps reduce silly mistakes and builds number sense.

2️⃣ Double and Halve

This trick is perfect for multiplication. If one number is even, halve it — and double the other. The answer remains the same!

For example:
25 × 16
👉 Half of 16 is 8
👉 Double 25 is 50
Now solve:
50 × 8 = 400

Isn’t that smoother? My students love this one!

3️⃣ Rounding and Compensating

Sometimes, adjusting numbers makes calculations quicker.

For example:
49 + 38
Round 49 to 50 (add 1) and 38 to 40 (add 2).
50 + 40 = 90

But you’ve added an extra 3 (1 + 2), so subtract:
90 - 3 = 87

A great way to sharpen estimation and accuracy!

4️⃣ Multiplying by 5, 10, and 100

Multiplying by these numbers is all about pattern spotting.

Multiplying by 10: just add a zero!
Multiplying by 100: add two zeros!
Multiplying by 5: halve the number, then multiply by 10.

Example:
42 × 5 = (42 ÷ 2) × 10 = 21 × 10 = 210

Once you master this, you’ll save loads of time during exams.

5️⃣ Using the Difference of Squares

This is one of my favorite mental math shortcuts, especially for older students.
If you spot a difference between two squares:

a² - b² = (a + b)(a - b)

For example:
102 × 98 = (100 + 2)(100 - 2) = 100² - 2² = 10000 - 4 = 9996

Fast and impressive, isn’t it?

6️⃣ Memorizing Key Multiplication Tables

Yes, I always say — you must memorize tables, especially:
1-20, 25, 50, 100, and 11, 12, 15, 19!

Why? Because tables are the foundation of all mental math.
In fact, I’ve designed a Multiplication Table Course at Welcome2Maths where I help students master tables up to 10,000 using fun patterns and tricks — no cramming, just smart learning!

💡 Final Thought:

Mental math is not about doing things the hard way — it’s about knowing little secrets to make big calculations easy. These strategies save time, boost confidence, and reduce exam stress.

I always tell my students: the more you practice, the more natural these tricks will become. And guess what? If you want to master them step by step, you can always check out my Master Calculation Course or join me for 121 Live Math Classes where I guide students personally.

👉 Let’s make math fun, one trick at a time!