Here is a picture of a problem we did together.
- Stack the problem vertically.
- Draw chart with the “whole” number (the largest number).
- Use “magnifying glass” to decide if we need to borrow and unbundle from another place value. If you do, X out a circle draw an arrow and then draw the 10 units. Don’t forget to X out the one you unbundled (moved).
- If you unbundled (borrowed) make sure you show that in the vertical form. Your numbers and picture should always match.
- Now, starting with the Ones column, X out the number of ones you are subtracting. Write the number left at the bottom of the picture, and write the number under the Ones column on the vertical form.
- Repeat Step 5 for the Tens column, and then the Hundreds.
- You should now have the same number at the bottom of your chart as you do in the vertical form.
- Lastly– CHECK by Adding. You add the answer and the number you subtracted. The goal is to arrive back at the original number that you started with. Show your work. Students may choose the best strategy for the numbers they are adding – arrow way, number bond, or vertical form with chart.
If you arrived at the original number, you did it correctly! If not, try again.
Here is a video that I hope will help clarify the chip and chart method.