A Decimal point (sometimes known as a ‘decimal separator’) is usually written as a point or a dot and is used to separate the whole part of a number from the fractional part. We understand this through place value. The connection between decimal numbers and fractions is essential to helping children understand decimal numbers and will be explored in the next section.
What are Decimal Numbers?
Decimals are used to write a number that is not whole. Decimal numbers are numbers that are in between whole numbers. An example of this is 12.5, which is a decimal number that is between 12 and 13. It is more than 12, but it is less than 13. It’s essential to note that decimal numbers are the same as fractions, except they’re expressed differently. Continuing with the previous example, 12.5 is the same as the mixed number 12 ½. It is true no matter how complicated the decimal is. For example, the number 0.75 is the same as ¾. If you wanted to, you could take this further and say that 0.75 is equivalent to 75%.
How to teach decimals
One of the most excellent ways to explain decimals to your class or children is through blank hundred-number squares or even ones filled in to highlight decimal numbers. First, however, children must understand how decimals relate to whole numbers. So, when talking about decimals, it might be best to explain that a whole number is split into multiple, smaller parts. Below is an image that showcases this learning strategy.
When teaching decimals, think about how you often use them in your life. One of the most significant daily uses of decimals is using money. The decimal in cash relates to a fraction of the whole value. For instance, if you are working with dollars, the decimal point shows the fraction of a whole dollar. Whatever currency you use with your class or at home with your child, you can show them how decimals work cheaply and easily. There are even some virtual ways of showing this if you don’t have any coins handy.
You can also use the money to help explain equivalent decimals or ensure you explain them to your children adequately. For example, children must know that decimals 0.7 and 0.70 are equal, especially in everyday contexts such as money or weight. They also must understand that changing the numbers before the left digit won’t change the value, so if a number is 005, it is still 5.
Decimal points have a purpose: to separate the ones and the tenths. You can visually show children this. For instance, for 25.35, you would say twenty-five and thirty-sixth hundredths.
You can also show children how helpful the decimal point can be when stacking up numbers in sums. Keeping decimal points in line can help children to complete sums more effectively.
