Mental Arithmetic and estimation

In this blog post I will be talking about the use of mental arithmetic and estimation in math problems. One of the reason that I am picking this topic is that so often children today do not have the skills needed to do simple problems in their head or to do simple estimations, which is often needed in daily life as the kids get older and head off to college or jobs. Here are some ways to teacher mental math to elementary students.

One way is to have the traditional worksheet designed to help children learn the basics quick and fast. This can be done online quick and easy.

One of the ways to teach mental math is to work on easy combinations of multiples of ten. This is also referred to as adjustment. In this method each number being added is modified to a different number to minimize the mental effort that required by adding zero to the number. For example, if we wanted to add the numbers 33, 35, 37 and 31 and wanted to do it mentally we would adjust the numbers to 30, 40, 40, 30 and then it would be simpler to add, the answer being 140. If we look back at the numbers 33, 35, 37, and 31, it would be difficult to see that the numbers come close to 140 without adjusting them. In the case of the unadjusted numbers they add up to 136, which is really close to the 140 we came up with after the adjustment.

A nice way to learn to round is to bring real life examples of when rounding would be useful to them. In school when I was young we learned to round but we weren't given any real world experience with it, making it seem useless in some ways. I think that a good way to learn it would be to have kids create a list of some sort, either of food or of items they would like to buy etc. Then have them find the prices of the items (or provide prices to move the activity along). Then show kids how to go about rounding what each item is going to cost. The following video is useful in teaching kids how to round, which will help them learn how to correctly estimate

I hope you found this lesson on metal arithmetic and estimation useful in helping teach young children the necessary tools for lifelong success of these concepts!!