This month, for Thursday Tool School, I am featuring tools to help students develop an understanding of fraction operations. Last week, I shared an idea for helping students understand how to add fractions and connect the actions to that of whole numbers. Today, I want to dig a little deeper with subtraction. Specifically, today’s post is about subtracting fractions with regrouping.
Once again this week, I have a Teaching Channel video that I’d like to share. Click the video link below to watch a 4th grade teacher teaching her students how to subtract fractions with regrouping using a pizza analogy.
The manipulatives are emphasized during the first five minutes of the video, so you can stop watching the video after that point.
Can’t see the video? Click here.
After watching the video, consider the following:
- How does the fraction manipulative help students explain what regrouping “looks like” with fractions?
- Why is a “think aloud” an important part of making our thinking transparent?
- In what ways could the teacher have used the manipulative to engage the students more?
While I love this video and appreciate how the teacher used stories and pizza to help students apply their understanding of fractions to develop the regrouping skill, I would have liked to see more student use of the manipulative. In fact, fraction circles mimic the “pizzas” that were on the board and would have allowed the students to trade a whole for fractional parts so that they could physically remove the pieces that needed to be subtracted. After students have had successful experiences with the model and have a good visual to guide their work, then move to just the math.
In addition, I want to encourage you to use sound mathematical vocabulary and strategies during your lesson. The term “borrowing” is technically incorrect and should be referred to as “regrouping” instead. Lastly, you may have watched past the 5-minute mark and noticed the teacher discuss a shortcut for determining the new numerator after regrouping. This is a shortcut and should be treated as such. Please invest the time to have students understand the process for determining the regrouped fraction.
Sound Off! How do you use models and manipulatives to teach fraction skills?