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Tips for Adding and Subtracting Fractions with Unlike Denominators

Fractions are tricky. Some kids seem to catch on right away and others just struggle to conceptualize it. Teaching fractions to 4th and 5th graders is very vocabulary heavy and there are fraction concepts that seem counterintuitive to what they just learned in place value. Here are a couple of tips and tricks for adding and subtracting fractions with unlike denominators.


Adding and Subtracting Fractions with Unlike Denominators

1. Use Fraction Tiles to Add and Subtract Fractions

By upper elementary, the fraction tiles shouldn't be new to your students, but they still make a huge impact. I love to start with them on day one to refresh the concept of fractions. I usually have them find "all the fractions equal to a half" and so on. I also like to have them find fractions that cannot equal a half. For example, fifths fraction tiles cannot equal a half.


I hesitated posting this picture because my table is such a HOT MESS, but that's real. 😝That was my super busy, super messy, guided math table.


Students using manipulatives to add and subtract fractions


I keep the number tiles around as long as they need them. I find, when they don't need them anymore, they don't want to use them.

2. Adding and Subtracting Fractions with Unlike Denominators using a Number Line

This was a great activity for equivalent fractions and fraction number sense. I used tape as a number line, I wrote the fractions on post-it notes, then passed them out for the group to place them on the number line. I did not let them move anyone else's fraction until the end.


Great for

✅ equivalent fractions ✅ fraction number sense ✅ comparing denominators


Students using a number line to add and subtract fractions

3. Factors of 24

Before I teach common denominators and adding and subtracting fractions to fifth graders, I like to highlight the number 24. The number 24 is a multiple of a lot of numbers (1, 2, 3, 4, 6, 8, 12, 24). Creating a circle map or brainstorming web of theses factors seems helpful especially for students who don't know their 4, 6, or 8 facts.


Factors poster

4. Add and Subtract Vertically

This was a game changer for my students. They were struggling with seeing common denominators. When I set up the problem vertically, the kids were able to see the how to create the common denominators and add. It really helped with problems in which they needed to regroup.



Adding fractions with unlike denominators vertically

adding and subtracting fractions worksheet

5. Four Square Fractions


I learned these four steps to adding and subtracting fractions from a co-worker. Setting up a four square board helps them remember that they have to find common denominators. This becomes particularly important when they start having to multiply and divide fractions. Here are the four steps of Four Square Fractions:

Box 1: Write the fraction equation.

Box 2: Find the Common Denominators

Box 3: Rewrite the equation vertically. Find equivalent fractions.

Box 4: Solve



Subtracting fractions with unlike denominators


subtracting fractions with unlike denominators

6. Task Cards


I have a task card center ever week. It is usually a review center of something they've already learned. For example, I would use this equivalent fractions pack for my 5th graders starting adding fractions with unlike denominators.

Different types of task cards I like: ✅Old fashioned paper task cards I like task card review because students can work together and talk to one another about the problems. I also like to use them for Cooperative learning activities like Quiz-Quiz Trade.

Equivalent Fractions Task Cards


7. Practice, Practice Practice!

Nothing beats good old-fashion practice. I do a lot of practice on white boards in small groups and independent practice with worksheets.


Fractions Color By Code Worksheet

Hope these small tips help your students conquer their math unit. If you're looking for math resources, I would love for you to check out my White's Workshop Teacher Pay Teachers store.


white's workshop name

White's Workshop button


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