# Decimals Using Base 10 Blocks and Money

Last week, I shared an activity that you can use when introducing fractions with denominators 10 & 100. Click here to read that blog post. It includes a freebie for your guided math groups!

Today’s blog post includes a math mat that will helps students represent decimals in various ways. In fourth grade, students are expected to “use decimal notation for fractions with denominators 10 or 100.”

## Use Base 10 Blocks to Represent Decimals

In the example below, students use base 10 blocks to build five-tenths. The flat represents 1 whole. Each rod represents 1/10 of the whole, so you need five of them to build 5/10.

The second picture shows how to model 1.25 using the base ten blocks. Again, this is a great way to show decimals in expanded form.  ## Use Money to Represent Decimals

In the following examples, student use money to represent decimals. Dimes represents 1/10 of a whole, because you need ten dimes to equal \$1.00 (one whole). Pennies are used to represent hundredths, because you need 100 pennies to equal one whole or one dollar.  ## Need resources for your math centers? 