Using a number line to find the difference between two numbers (to subtract) is a mental maths strategy that many of us do without realising. To help children get used to the mental strategy, we teach them to draw the line to visualise the difference, and then make jumps (the fewer, the better).
If you’re not convinced, think about how you might calculate 2003 – 1995 or 180 – 95… Very few people would be able to use a traditional column method to get the answer quickly and accurately. We do teach the column method as a written maths strategy, too – but that’s better for bigger and more complicated numbers!
httpv://www.youtube.com/watch?v=NHEng-jRWlQ’ >Subtracting using a number line