5 Common Fraction Mistakes Teachers Make (And What to Do Instead)

Let me tell you about the year I thought I was nailing fraction instruction.

My lessons were clear. My examples were solid. My worksheets were... well, they were worksheets. But they covered all the standards!

And yet, come assessment time, half my class was still confused. A quarter thought 1/3 was bigger than 1/2 "because 3 is bigger than 2." And I was standing there thinking: What am I doing wrong?

Turns out, I was making some really common mistakes.

Mistakes that pretty much every elementary teacher makes at some point. Mistakes that have nothing to do with how hard you're working or how much you care.

If your fraction unit keeps going sideways no matter what you try, you're probably making at least one of these mistakes. (I was making three of them. At the same time. No wonder my students were confused.)

This is the big one. The mistake that causes more fraction confusion than anything else.

Here's what it looks like:

Day 1 of equivalent fractions, you teach: "To find an equivalent fraction, multiply the numerator and denominator by the same number. So 1/2 = 2/4 because 1×2=2 and 2×2=4. See? Easy!"

Your students nod, write it down, and seem to get it.

Day 2, you give them practice problems: "Find three equivalent fractions for 2/3."

And half your class writes: 2/3 = 4/6 = 8/12 = 16/24 ✓

Looks good, right?

Then you give them a word problem: "Maria ate 2/4 of a pizza. Her brother ate 1/2 of the same pizza. Did they eat the same amount?"

And those same students write: "No, because 2/4 and 1/2 are different fractions."

Wait. What?

Here's what happened: They memorized the procedure (multiply top and bottom by the same number) without understanding the concept (these fractions represent the same amount).

They can follow the algorithm. They cannot explain why it works. And the second you ask them to think about fractions instead of just manipulating them, they fall apart.

Show them FIRST that 1/2 and 2/4 are the same amount. THEN teach the algorithm.

Give them fraction bars. Or circles. Or number lines. Have them shade in 1/2 on one bar and 2/4 on another bar.

Ask: "What do you notice?"

When they see with their own eyes that the shaded amounts are identical, the algorithm makes sense. It's not a random rule—it's a shortcut for something they already understand.

The algorithm should be the last step, not the first.

I get it. You have 47 fraction standards to cover before state testing. Equivalent fractions is just one skill. You've got comparing, ordering, operations, word problems...

So you spend 3 days on equivalent fractions and move on.

Except here's the problem:

Equivalent fractions isn't "just one skill." It's the foundation for literally everything else you're going to teach about fractions.

Can't compare fractions? That's because they don't understand equivalence.

Can't add fractions with unlike denominators? That's because they don't understand equivalence.

Can't simplify fractions? Yep. Equivalence again.

When students don't truly master equivalent fractions, every single fraction skill that comes after it is built on shaky ground. And then you're reteaching equivalent fractions in the middle of adding fractions, and it's a mess.

Slow. Down.

I know the curriculum guide says you should move on. I know state testing is coming. I know you feel behind.

But spending 7-10 days on equivalent fractions (instead of 3) will actually save you time later. Because you won't be reteaching it in the middle of every other fraction unit.

Make sure students can:

• Explain WHY equivalent fractions are equivalent (not just follow the procedure)

• Recognize equivalent fractions in different formats (visual models, number lines, equations)

• Generate equivalent fractions without having to multiply/divide

• Use equivalence to solve problems

Then move on. Not before.

Picture this:

You're teaching comparing fractions. You explain: "To compare fractions with different denominators, find a common denominator, then compare the numerators."

Student A gets it immediately. They've been ready for this since last week. They're sitting there bored while you explain it three more times.

Student B is completely lost. They're still not solid on what a denominator is. Your explanation might as well be in another language.

Student C sort of gets it but needs to see it visually. Your abstract explanation isn't clicking yet.

You just taught to Student C. Student A is bored. Student B is drowning. And tomorrow you'll do it all again.

This isn't a you problem. This is a one-size-fits-all instruction problem.

Stop teaching one lesson to 25 different students.

I know that sounds impossible. You can't create 25 different lesson plans. You don't have time to sit with each student individually.

But here's what you can do:

Teach one lesson with multiple entry points.

Introduce the concept to the whole class. Then give students practice at their level.

Some students need more visual models and smaller numbers. Others are ready for grade-level problems. A few need challenge problems to stay engaged.

Same concept. Same format. Different difficulty.

I use a three-tier system (I label my papers "square" for foundational, "triangle" for grade-level, and "circle" for challenge) where students work on the same skill at different levels.

It's not as obvious who's doing what. Everyone's learning.

You teach once. Students practice at their level. Everyone grows.

Here's a belief I had to unlearn:

"Visual models are training wheels. Once students understand fractions, they don't need them anymore. The goal is to get them working abstractly as fast as possible."

This is wrong. So, so wrong.

Here's the truth:

Visual models aren't training wheels. They're the foundation. And even students who can work abstractly benefit from continuing to use visual models.

Research shows that students who use visual representations alongside abstract algorithms develop deeper understanding and make fewer errors. Not just struggling students. All students.

But here's what usually happens:

We use visual models for a day or two with the whole class. Then we move to abstract practice (equations, worksheets, no pictures).

Struggling students get left behind because they needed more time with the visuals. Advanced students miss the chance to deepen their understanding by connecting visual and abstract representations. Students who have already memorized the algorithm but don't really understand it get missed.

Keep visual models in the mix. For everyone. All year.

This doesn't mean every problem needs a picture. But visual models should be available, encouraged, and regularly used even when students are working at higher levels.

Advanced students should:

• Draw models to explain their thinking

• Use visuals to check their work

• Teach struggling students using models

Struggling students should:

• Have access to fraction bars, circles, number lines

• Start every new concept with concrete visuals

• Move to abstract when they're ready (not when the curriculum guide says)

The goal isn't to stop using visual models. The goal is to flexibly move between visual and abstract thinking.

I used to think students needed exactly 20 problems per skill.

I'd print a worksheet with 20 equivalent fraction problems. Students would do them. I'd grade them. We'd move on.

Two problems with this:

Problem 1: Some students needed 5 problems, some needed 50.

The student who got it after 5 problems sat there bored for the other 15. The student who needed 50 problems didn't get nearly enough practice and then failed the assessment.

Problem 2: Even when students needed the practice, they hated doing it.

Boring practice doesn't stick. Students rush through just to be done. They're not actually processing the math—they're just filling in blanks.

I needed more practice for some students and less for others. And I needed all of it to not feel like drudgery.

Give students enough practice for their level. And make it engaging enough that they actually want to do it.

This looks like:

• Practice activities with built-in differentiation (students work at their level)

• Formats that feel like games, not worksheets (task cards, mazes, color-by-code, escape rooms)

• Self-checking so students get immediate feedback

• Flexibility so students can repeat what they need and skip what they don't

It's much less common for my students to complain about "too much practice" when it's in a game format. I've had students volunteer to work on fraction activities during free time.

Notice a pattern in all these mistakes?

They all assume students are learning the same way, at the same speed, with the same needs.

And that's just... not how learning works, but you know that.

The fix isn't more lesson plans. It's smarter systems.

Systems that let students:

• Build conceptual understanding before memorizing procedures

• Spend enough time on foundations before moving forward

• Work at their own level without being separated into obvious "ability groups" all the time

• Use visual models as long as they need them

• Get enough practice in formats that actually keep them engaged

When you have systems like that in place, everything gets easier.

If you're reading this and thinking, "Okay, I'm definitely making at least three of these mistakes... now what?"

Here's where to start:

You may already have my free Equivalent Fractions Task Cards. If you haven't used them yet, start there this week.

They're designed to avoid all five of these mistakes—they build understanding before algorithms, they're differentiated, they include visual models, and they make practice feel less like work.

See how your students respond.

If they love them (and you love not making these mistakes), here's what helped me build a better fraction unit:

The Fraction Task Card Bundle has everything you need to teach fractions without making these common mistakes:

These aren't just task cards. They're a system for teaching fractions the way students actually learn—not the way curriculum guides say we should.

Or keep using the free set and implement one change at a time. Either way, you're not making these mistakes because you're a bad teacher. The system is broken, and there's just not enough time in the day.

Pin this post for when you're planning your fraction unit. And if this helped you see what's been going wrong, share it with another teacher who's wondering why fraction instruction keeps falling flat.