Number Forms


Part of using base-ten numbers correctly is understanding how to express the same number in different forms.

Let’s use: 273. This is the base-ten numeral written in standard form.

Next, let’s express 273 in unit form. To help, your child may label with a place value chart. Hundreds column, tens column, ones column. We see that two hundred seventy three is made up of three ones, seven tens, and two hundreds. This is unit form.

Next, we’ll show expanded form. Working from standard form… What is the value of three in the ones place? Three! What is the value of seven in the tens place? Seventy! What is the value of two in the hundreds place? Two-hundred! Your child will use this number bond to write the expanded form: 200 + 70 + 3 = 273. This is expanded form.

Let’s move on to number name. Sometimes it’s called word form. What you say is what you write: Two-hundred seventy-three. This is the number name.

It is challenging to move between forms, so lots of practice can help! Give your child a number expressed in one form and ask him to write a different form. Then, your child will understand the base-ten numeral value – whatever form it’s in!

And that’s good to know.

Grade 2 Common Core Standards
Number & Operations in Base Ten: Understand place value.

(2.NBT.1) Understand that the three digits of a three-digit number represent amounts of hundreds, tens, and ones.
(2.NBT.3) Read and write numbers to 1000 using base-ten numerals, number names, and expanded form.