Teaching Fourth Grade Fractions & Decimals: Everything you Need to Know

In fourth grade math, the giant list of standards kids have to master can feel overwhelming, especially for new teachers (grade changers, we see you, too!). There’s problem solving, factors & multiples, place value & rounding, division computation, angles, classifying quadrilaterals, line plots, measuring, the list goes on. And that’s not even counting the seven (7!!!) very detailed NF (numbers- fractions) fraction & decimal standards. Seriously, two of those standards even have multiple parts!! And the language they used to write these standards can make anyone’s head spin. It’s enough to make any fourth grade teacher in her very disorganized and mildly stinky supply closet (definitely not based on real life or anything, guys…).

So what’s a teacher to do? Delete that page of the PDF? Accidentally shred the page with the fractions standards? My dog ate the fractions? All perfectly reasonable responses, I promise. For me, my go-to solution for feeling overwhelmed about anything in general (other than hiding in the closet) is to break it down into manageable chunks.

Psst… If you’re a 3rd grade teacher, click here for the third grade version of this blog post.

Breaking Down the Fourth Grade Fractions & Decimals Standards

Teaching fourth grade fractions can be daunting because there are 7 fourth grade standards, but these are really separated into two parts: Fractions (standards 1-4) and Decimals (standards 5-7). Cool. The first two (standards 1-2) are about equivalence and ordering fractions. Okay, cool, we can do that! The second two (3-4) teach students to add, subtract, and multiply fractions. That sounds daunting, but it’s a little easier to manage when we realize it’s only adding & subtracting with like denominators and it’s multiplying fractions by whole numbers. (Sorry, 5th grade teachers, we leave that stuff for you!). And then there’s the decimal section, and we’ll worry about that later (ie, farther down this page). Plus, two of the decimal standards are really two sides of the same coin (converting fractions to decimals and decimals to fractions), so two birds, one stone on that one.

Okay, let’s dive in! If you feel overwhelmed, just stop and focus on one section or standard. If you want someone to just do it for you, you’re in luck, because I already did!! You can find my complete, detailed Fourth Grade Fractions & Decimals math unit here. It’s also broken down into parts for you, in case you feel like you just need a hand with one or two of the standards. Just follow that same link and then click on the standard you want.

Teaching Equivalence & Ordering Fractions

These two standards go nicely together. If your kids understand equivalent fractions, then they can use those as a benchmark when comparing and ordering fractions, and it gives them another strategy in their toolkit.

I usually start in the same place for both of these concepts. We spend a lot of time coloring in fraction bars and working with fraction pieces. It’s not enough for kids to just do cute activities like coloring in their name and writing that their name is 1/5 the letter C, or to build designs with circle fraction pieces. These kinds of activities and craftivities are fun and cute, but the students aren’t interacting very much with the concepts of fractions.

Instead, try having them color or gather all the unit fractions (1/2, 1/3, etc.) and lead a discussion about the patterns they see. The fact that larger denominators make smaller pieces is a concept that confuses even many adults. I always related it back to sharing a cake. The more people you have to share with, the smaller each piece will be.

If your kids need a review or extra practice with fractions on a number line, try this FREE Fraction on a Number Line Teamwork Challenge. It’s a group activity, so you’ll be able to see overall how well your kids understand the concepts. Plus, your stronger students can help the group and make it a great review or introduction to your fraction unit. Not to mention that it has over NINETY THOUSAND downloads, so you know it’s good!

Go get it, it’s FREE!!

Teaching Equivalent Fractions

4.NF.1: Basically, kids need to understand that thing where, if you multiply the numerator and denominator by the same number, you get an equal fraction. (Example: 1/2 x 3/3 = 3/6, which is equal to 1/2.) Sadly, many of us were taught this as a rule, without any understanding behind it. Obviously, that’s not a great idea, as kids need to understand these concepts to be able to use them an apply them. Once kids understand it, they can use this concept to find and generate equivalent fractions.

Okay, y’all. The trick here is… FOLDING. Fold a paper in half, color in half of it. Fold it again so it’s in 4ths, and when you open it up, you can see that the 1/2 is equal to 2/4. I have a whole other blog post on teaching equivalent fractions with folding, because it’s honestly one of my favorite lessons ever. (The aha! moments are well worth it!!)

Fraction bars and number lines are also super helpful here for helping students visualize equivalence. Break out those fraction clotheslines and fraction pieces from the previous lessons and ask lots of questions and have lots of conversations to help your students see the relationships.

Teaching Comparing & Ordering Fractions

4.NF.2: Comparing fractions that have the same numerator (1/3 and 1/4, eg.) OR the same denominator (1/4 and 3/4, eg.). That’s the key idea, and then there are other concepts and skills layered in to that. Kids can compare by creating equivalent fractions or using a benchmark (half, for example), keeping in mind that they can only compare fractions of the same whole. They should be able to use <, >, and =, and to justify their ideas.

Once your students have developed the basic concepts of fraction size, try the same activities, but with two of each piece (2/3, 2/4, 2/6, etc.). They’ll begin to extend their understanding that a bigger denominator means smaller pieces (assuming the numerator is the same, of course!).

By coloring two of each fraction piece, kids can see the pattern that 2/3 is much bigger than 2/6, even though 6 is bigger than 3.

Number lines really help here, as well. I love writing fractions on clothespins and having the kids put them in order. It’s an easy activity to differentiate by giving different students or groups different sets of clothespins. You can also challenge your stronger students to make the spacing even between the fraction on their number lines. Pro tip: I don’t actually like using clotheline for this, though. I used sentence strips because they were more manageble. Plus, the kids can fold them and see the marks to help them find where the fractions should be placed.

One of my go-to activities for developing higher order mathematical thinking skills is creating a sort. Sorting things into groups forces students to think about their differences and similarities, which involves lots of good critical thinking skills. Especially if students can’t create the whole fraction number line on their own, sorting the fractions into groups (less than one half, equal to 1/2, and more than one half, eg.) helps them begin to compare and order fractions. To see how I used sorting fractions in my classroom, check out this blog post with more information.

A key concept that sometimes gets forgotten when teaching comparing and ordering fractions is the concept of the whole. It’s important to help students remember that they are comparing these fractions in relation to the whole.

Psst… Want a ready-made, in-depth lesson plan to help you get started teaching equivalent & comparing fractions (standards 4.NF.1-2)? Get it here!

Teaching Adding, Subtracting, & Multiplying with Fractions

Once your kids have a solid foundation of understanding the sizes of fractions, they can begin to do computations with them. At first, multiplying fractions sounds scary, but keep in mind that a lot of the multiplying kids will do in fourth grade is based in repeated addition.

Sometimes, thinking of multiplication like arrays or using repeated addition helps here. If your kids are really stuck, try going back to review some area/ array concepts, as those really help with the basic multiplication concepts. It might seem unrelated at first, but sometimes area or arrays can be the link that helps kids make that jump!

Teaching Adding & Subtracting Fractions with Like Denominators

(for unlike denominators, click here)

The key here is to make sure kids are adding fractions with the same denominator. Once we remove unlike denominators, adding and subtracting fractions is the same as adding and subtracting anything else. One apple plus one apple equals two apples. One third and one third equals two thirds. Same same, but different. Bonus points here because your more verbal students will be able to rely on the language to help them understand the numbers.

Teaching Multiplying Fractions

Basically repeated addition for unit fractions (unit fractions have 1 as a numerator). Example: 1/8 + 1/8 + 1/8 is the same as 3 x 1/8.
b: Same idea as 4.NF.a, but now we’re connecting that repeated addition to groups other than 1. For example, 3 x 2/5 (3 groups of 2/5s) is the same as 6 of the 1/5s. (Draw a picture, I promise it makes sense!)
c: Solve word problems using multiplication of a fraction x a whole number.

The trick with multiplying fractions is to simply use repeated addition. If your students have a solid understanding of the concept of multiplication, this should just be a natural extension of adding fractions. This standard is also a great place to stop and review and differentiate and work on problem solving.

Don’t let 4.NF.4b scare you. It’s just addition with groups of fractions.
This slide comes from my 4.NF.4 Multiplying Fractions math unit.

Teaching Decimals

Fourth grade is usually the first real introduction to decimals. Of course, students will have some experience working with decimals from learning about money, but now they will begin to compare decimals and work with the relationship between fractions and decimals.

Converting Fractions to Decimals & Decimals to Fractions

4.NF.5: Students need to change fractions that are /10 to fractions that are /100. (So, 3/10 = 30/100.) They can use that to add x/10 and x/100. In other words, add 4/10 and 57/100 by making 4/10 into 40/100 first. This is an important step for them to learn to add fractions with unlike denominators in the future.
One way to get to the ‘aha’ moment here is by using money. Three dimes is the same as 30 pennies, or 3/10 = 3/100. Having the kids use concrete materials like Base Ten blocks or coins helps them start to naturally understand the connection here and avoid making errors.

4.NF.6: Write fractions with /10 or /100 as decimals. (Examples: 5/10 = 0.5 and 5/100 = 0.05) This is a super important concept, connecting fractions and decimals. However, if you’ve done your job in getting your kids to understand fractions as part of a whole and understand place value, then this can actually be a really simple standard for kids to conquer. By the time I got to this one with my own students, it was a quick lesson because it just made sense for them.

Okay, so this one is a ‘two-fer’, which we desperately need at this point. These two standards cover working with fractions that have 10 or 100 as denominators. Students need to understand how to convert between /10 and /100 and how to change those to decimals.

This is another place where your more verbal students might find an advantage. If you read the fractions and decimals in words, they are exactly the same. For example, ‘three tenths’ could be 3/10 or 0.3. Reading a fraction or decimal out loud can help students come up with the other format.

Fortunately for us, there are tons of good concrete and visual models to help kids understand these conversions. I used the hundreds, tens, and ones place value/ base ten blocks a lot in my classroom. The key to this is that students have to understand that in this model, the hundred block is one, like one dollar. Then, the tens become tenths and the ones become hundredths.

Of course, using money and dollars, dimes, and pennies is another more obvious model for teaching this concept. Kids will need to get that a dime is 1/10 of a dollar (because 10 dimes = 1 dollar) and that a penny is 1/100 of a dollar (because 100 pennies = 1 dollar).

Comparing Decimals

4.NF.7: This is the decimal version of 4.NF.2. Here, students can compare decimals up to hundredths. The same concepts and skills are layered in here (hello, sprialed review!) as are in the comparing fractions standard. Kids need to be aware of comparing within the same whole, be able to use <, >, and =, and to be justify their responses.

Decimals are usually new for fourth graders, and we’re at the bottom of a page with a lot of information. It can be easy to get overwhelmed and just give up and just let the fifth grade team deal with it. But don’t stress, this concept can actually be one of the easier ones for kids to master.

Lots and lots of number lines for decimals!! It helps to make ones for tenths and then ‘zoom out’ and make one for hundredths. It’s tedious to make a whole number line for hundredths, but I had the kids work in groups and it was really helpful for them to see the whole thing, from 0-1.
Labeling with 0.8 and 0.80 helps kids see the connection between 8 tenths and 80 hundredths, which helps with converting fractions as well. Just like whole number place value, it’s important to see the patterns and practice counting along the number line!

Fourth graders work with decimals to the hundredths. Other than having to learn to pronounce “tenths” and “hundredths” (which we all know just ends in them spitting everywhere, raspberry style), most kids actually have a lot of background knowledge to rely on for this standard. Students have been working with money concepts for years now (hopefully, but you know, pandemic and all…). They often have a pretty good understanding of dollars and cents and have seen prices written in decimal formats ($2.99,eg.). We teachers can take advantage of that knowledge and use it build out their understanding and help them compare decimals.

This is one example I used in my class to help students learn to justify their reasoning with visual models and written explanations when comparing decimals.
(You can get this whole math unit here.)

If your students need lots and lots of practice with comparing decimals, that can actually be a good thing. It’s a great chance to work on how students explain their work and justify their thinking. Have them draw and label lots of visual models and write out explanations of their thinking. They’ll strengthen their understanding of the concept and get better at explaining their reasoning.


Still feeling overwhelmed?? I got you! I’ve spent hundreds of hours designing and creating an entire math unit to cover all of these standards. It’s fully aligned to the Common Core standards, and every lesson is differentiated. My fractions & decimals unit meets kids where they’re at and breaks down the concepts so kids will truly ‘get it.’ It’s full of detailed lesson plans, engaging activities, clear visuals, great discussion questions, printables, assessments, vocab cards, everything you need to help all your students master the fourth grade fraction standards. Get the entire unit or just the parts you need here.

Teacher-Author Note: This post is a work in progress and I’m continually adding ideas & images to provide more content. But I wanted to publish it sooner rather than later, because I know many teachers are teaching fractions at this time of year and could use some help & support.