Are you ready to help your 5th graders conquer the world of mixed number subtraction? Well, get ready to regroup with this easy strategy. Don’t rely on the algorithm alone when teaching subtracting mixed numbers with regrouping. Use virtual manipulatives to show students what regrouping is.
What is subtracting mixed numbers with regrouping?
First, let’s review what it means to regroup. Regrouping is a fancy way of saying “borrowing” or “trading” when subtracting a larger number from a smaller one. For example, if you wanted to subtract 3 and 2/3 from 4 and 1/3, you’d need to regroup by borrowing a whole number from the 4 and breaking it into fractions.
Easy peasy, right? Your students may not think so initially, but they’ll catch on quickly.
But there’s not enough time!
Math teachers everywhere have a bazillion things to teach and not nearly enough time. It’s tempting to get the show on the road and jump straight to the algorithm. This will work fine for some kids but leave others lost and confused.
To ensure the algorithm doesn’t come crashing down like a house made of cards, start by building conceptual understanding. It takes a little time, but building a solid foundation pays off in the long run. Helps students understand what is happening by using hands-on experiences.
virtual vs. physical manipulatives
Manipulatives are great for helping students visualize the process of regrouping mixed numbers, but they can be a hassle to manage. Organizing manipulatives for the day’s lesson takes time. Then no matter how careful you are, no matter how many times you tell students to search the floor, there’s always a lone fraction piece that gets discovered long after the materials are put away. Good grief! Where exactly does that ⅙ piece go???
With virtual manipulatives, each student gets the materials they need delivered to them with very little prep from the teacher. Not only are the manipulatives inexpensive, but they are also easy to use.
mixed number subtraction with manipulatives
Want to show your students what is happening when you regroup? Layer fraction strips so they can “exchange” a whole for an equivalent number of fraction pieces.
For example, students can delete the bottom whole strip and find six sixths underneath. This helps them rename the mixed number, and after a few repetitions, students can rename the mixed number without using the manipulatives.
It’s that simple
By practicing regrouping with hands-on experiences, students can develop a solid understanding of the process, which makes it less likely for them to make procedural errors when subtracting mixed numbers. Students will gain more confidence in their mathematical abilities and feel they can conquer the world of math.