Before children are ready to explore the meaning of expanded form, they should have a solid understanding of place value. If your children need more instruction in place value before beginning expanded form, we suggest looking at http://www.thecurriculumcorner.com/2012/09/16/counting-ones-tens-and-hundreds/
These lessons were created with the help of Cathy’s student teacher, Joel Larrison.
We suggest beginning by using manipulatives such as base 10 blocks or bundles of straws. We also recommend beginning with numbers less than 100 and moving into numbers with three digits.
An Introduction To – begin helping students understand expanded form, give them an amount of counters. Have them tell you the total number. Then, ask them to identify how many hundreds, tens and ones the number has. Record these answers on the board. Next, record the value of each. For example, if students have 2 bundles of 100 the value of the digit in the hundreds spot is 200. When you have recorded the value of each digit, you are ready to show students what expanded form looks like. Below the chart you created, write an equation using expanded form. The equation for the picture to the left would be 200 + 70 = 270. Repeat this activity until students begin to understand the meaning of expanded form.
Place Value Stacks This activity was created to give students a visual that helps them understand expanded form. Print and laminate the number cards. You can then stack one number from each place value position to create a big number. As you take the numbers apart, there is a visual that helps students understand and write the number in expanded form. (Pictures of this activity in action coming soon!)
Number Folds This is a visual, manipulative activity to help students visualize the number being stretched. Cut this paper into four, long strips. Fold the paper so that students have three boxes showing to record the number. Students then pull apart their number and add zeros in the empty boxes. This motion transforms the standard number into an expanded form number.
Expand a Number Give each student a sheet and three dice. The children roll their dice to create a three digit number. They will record the number in different ways.