Parents often ask me what the Grid Method of Multiplication is and why their children are being taught this in primary maths at school.
Grid Multiplication is designed as an interim calculation method, to promote children's understanding and develop their mathematical jottings. It's designed as a stepping stone towards the more traditional method of Column Multiplication (the method many of us are familiar with). The Grid Method of Multiplication is designed as a multiplication tool to help children understand the fundamentals of maths, one of the key aims outlined in The National Curriculum for England (2013).
The National Curriculum, produced by the Department for Education, promotes the teaching of maths through three main aims:
"to become fluent in the fundamentals of mathematics so that pupils develop conceptual understanding and the ability to recall and apply knowledge rapidly and accurately
to reason mathematically by following a line of enquiry, identifying and using mathematical language
to solve problems by applying their mathematics to a variety of routine and non-routine problems with increasing sophistication."
Before children learn how to multiply larger numbers using any written method, they need to understand the concept of multiplication (times tables). Children don't need to know all the times tables facts by heart (at this stage) but they do need to understand the concept of what times tables facts represent e.g. the repeated addition of the same number.
If your child doesn't yet know all their times tables facts, a multiplication mat is a handy resource that will help them, whilst learning this box method of multiplying (download your FREE copy - link at the bottom of the page).
From my experience, as a primary school teacher, children who are taught the Column Method of Multiplication too early have some success initially and appear to have mastered the method. However, a few months down the line, they often begin to struggle as they forgot the steps in the process. Children who are introduced to traditional methods too early often lack the understanding behind each step and how it contributes to the complete calculation. This leads to mistakes and the inability to identify where they have gone wrong. Learning maths by memorising processes is not recommended and can dent children's confidence in the long term. Children miss the opportunity to experiment and explore with numbers, helping them make connections in their understanding and develop mathematical reasoning.
The Grid Method of multiplication is designed to show children how to multiply each part of the number, through partitioning, reinforcing application of their times tables facts and multiplying multiples of 10 and 100.
How to use the Grid Method (Multiplication)
Like any new skill, it's best to start with small numbers: two digit numbers multiplied by one digit e.g. 35 x 4 =
Step One: Draw the multiplication grid (see picture). For the question 35 x 4 =, you will need two columns as 35 is made up of two digits (tens and ones).
Step Two: Partition your number and write the individual parts of the number in the grid (as shown in the picture).
Step Three: Multiply 30 x 4 (the best way to calculate this question is 3 x 4 x 10 =) and write the answer in the grid (see picture).
Step Four: Then multiply 5 x 4 and write the answer in the grid (see picture).
Final Step: Calculate your final answer by adding up the numbers you have jotted inside your grid. e.g. 120 + 20 = 140.
The Grid Method can be used for multiplying much larger numbers (see picture). For a three digit number you need to draw three columns and a four digit number you need to draw four columns and so on.
The Grid Method can also be used for multiplying numbers by a two-digit number. It requires two horizontal rows for each part of the multiplier (see the picture).
The Grid Method's sole purpose is to develop children's mathematical understanding in solving larger multiplication questions. Remember, it is a stepping-stone method towards the more traditional Column Method of Multiplication. The more traditional method is usually introduced when children's knowledge of times tables and multiplying by multiples of 10 and 100 is more secure.
Whilst the Grid Method is brilliant in developing children's understanding, it is not the most efficient method to multiply large numbers and therefore it is not a method that is designed to be used forever. It takes up more space than the traditional column method and can be more time consuming to complete.
Every child's learning journey is different. Some children may only use the Grid Method for a few weeks and pick up Column Multiplication soon after. However, some children will stay with this method for a number of years, as they develop a wider understanding of multiplication. The most important thing to remember is that children need a multiplication tool that they understand and can apply to a wide range of mathematical problems.
Maths is not a linear set of methods that we all apply in the same way. As children progress through the National Curriculum, they will become equipped with a series of methods that they feel confident in applying to calculations in school and in real life. Our aim, as teachers, is to develop confident mathematicians equipped with a range of calculation tools.
If you are looking for help with learning times tables, I have written a Maths workbook called the Busy Bees Times Tables Workbook available on Amazon. Don't forget to download your FREE Multiplication Mat too.
You might also find some of my other blog posts on Maths topics useful too:
Happy Multiplying.
Joanne Adams
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