The Power of Mental Math: Strategies for Quick Calculations

It is important to know how to fully work out a math problem; however, everyday life doesn’t always allow for that. You may not have a pen and paper handy or even access to the calculator on your phone (shocker right!). There is one thing you always have with you though…your mind. Mental math to the rescue! 

Some students love using mental math because they can arrive at the answer faster than having to work it out on paper. Others may feel some anxiety about not being able to write out the problem and keep track of partial answers. Mental math doesn’t always come naturally for everyone, so it is important to teach students strategies for using mental math. With practice, they can become mental math masters (say that five times fast). 

Did you know that different parts of the brain are used for various math skills? One study reported that estimation uses a different portion than the skills required to calculate exact answers. Recalling basic facts is linked to verbal memory, while estimation uses spatial knowledge that many refer to as number sense. Research has also found that our brains have a
“cluster of specialized nerve cells for processing numbers” and that much of math is processed through the visual system of the brain. This means that mental math is a great brain workout!

Mental math requires long-term memory recall, so continued practice of basic math facts and skills is important for that knowledge to be transferred into long-term storage. While mental math may not be part of your actual curriculum, it is very important to include it to aid students in the math skills needed for everyday life by improving their memory and mastery of basic facts. 

Origo One offers multiple videos with tips for teaching mental math strategies. Here are just a few of them: 

Addition

• Count on Strategy
• Make-Ten (or Bridge-to-Ten) Strategy for Addition

Subtraction

• Think-Addition Subtraction Strategy

Multiplication

• Use-Ten Strategy
• Doubling Strategy
• Build-Up Strategies
• Build-Down Strategies 

Division

• Think-Multiplication Division Strategy

Here are some other strategies to help teach and practice mental math. 

• Estimation: Much of the math we use in our daily lives doesn’t require an exact answer so teach estimation strategies. Click below for suggestions!
  • Estimation 180
  • 18 Estimation Activities for Kids
  • 20 Estimation Activities for Kids
• Mnemonic devices: Use acronyms or rhymes to help students think about the skills needed to mentally solve equations. Visit these sites for ideas!
  • Math Mnemonics
  • Commonly Used Mnemonics for Math
• Use the expanded form to break numbers into smaller parts (i.e. 283 = 200+80+3). This will make it easier to mentally add, subtract, multiply, or divide the number. 
• Build on with skip counting or number patterns
• Practice multiplying and dividing by multiples of ten using decimals. For example, move the decimal over to the right or left (i.e. 380 divided by 10 is 38 and 2.745 times 100 is 274.5) 

Games and activities for individuals, partners, or the whole class:

• Flashcards (for timed and untimed practice)
• Play Bingo where equations are called out and students locate the answer on their board
• Oral or taped problems: Give equations at decreasing intervals to improve fluency. A study was conducted on taped problems given at decreasing intervals allowing less time for students to answer resulting in increasing accuracy. This study also reported on the importance of basic math fluency to aid students in understanding more advanced concepts, decrease anxiety, and increase confidence and motivation within mathematics.

Online games: Some are free and others require subscriptions. Plus some sites may include games for other subjects you teach too! 

• Prodigy Game
• Math Playground
• Math Games
• Math is Fun
• MathNook
• Fun Kids Online Math Games

Let us know of other mental math strategies you have found helpful to teach your students!