Transitioning your students from basic addition to 2-3-digit addition can be tough sometimes! There are five 2-3 digit addition strategies I focus on in my classroom.
These strategies do not focus on the standard algorithm.
If you’re looking for 2-3 subtraction strategies, you can read all about them over on this post!
In this post, you’ll see pictures using my addition strategies resource, but you can implement these strategies with just paper and pencil!
Many of these strategies are for two-digit addition AND three-digit addition. I prefer to start with two-digit addition in my classroom and then apply them to three-digit addition.
A Quick Note Before You Teach 2-3 Digit Addition Strategies
One of the key factors in teaching students various 2 digit and 3 digit addition strategies is to help them DISCOVER these strategies. That means YOU as the teacher are participating more as a facilitator.
I know what you’re thinking… will my students really be able to come up with these strategies on their own? YES! It’s all about strategically guiding and helping them use and apply what they already know!
You can read all about getting your students talking and sharing math strategies over on this post covering number talks!
Addition Strategy #1: Hundreds Chart
First, if you’re starting two-digit addition, chances are your students have had a decent amount of exposure to a hundreds chart. I LOVE using this to start addition strategies.
Begin by using a large hundreds chart on the easel or interactive whiteboard. Write down a two-digit addition problem and ask students how they can solve it using the hundreds chart.
How does this strategy work? Basically students will circle, color, or highlight the biggest number. Then, they will jump down to add the tens, and then they can add the ones.
Addition Strategy #2: Base 10 Blocks
Next, you may have some students that may not be ready to move to more abstract strategies. They rely on base ten blocks, and that’s okay! They’ll get there eventually.
In this strategy, students use base ten blocks to add both numbers. Some students may need to use the physical blocks, while others may need to simply draw the blocks.
Addition Strategy #3: Break Apart
In this third strategy, students break apart the numbers into hundreds, tens, and ones to add. First I put a problem on the board and have students solve it in their heads. When they share, I listen very carefully and write how they solved it.
Many times students don’t quite know how to record their thinking, so that’s what you as the teacher are doing as you facilitate sharing addition strategies.
As you can see in the picture below, there are a couple of different ways your students might share how they break apart numbers to solve.
In the first and third strategies, both numbers are broken apart by place values. If you look at the second strategy, only the smaller number was broken apart so the student could count on from the bigger number.
Addition Strategy #4: Number Line
Next we have the number line strategy. This addition strategy is VERY similar to the break apart strategy. The only difference is that you’re recording the work on a number line.
Students can do this a variety of ways. Many times the most efficient way to use a number line is by starting at the biggest number and making jumps of hundreds, tens, and ones to count on the smaller number.
Addition Strategy #5: Fact Finder
This final strategy is one my students came up with that we use alongside any of our previous strategies.
Remember when you were teaching basic addition facts and you focused on ways to make 10 and doubles/doubles plus one? It’s time to pull that prior knowledge back out! (If you need basic addition fact strategies, you can read all about those in this post!)
Here are a few ways students can use their understanding of the ways to make 10 strategy. For example, since students know 4 + 6 = 10, then they also know 40 + 60 = 100. Or, they might notice that in 27 + 43, the ones place (7 & 3) is a fact that makes 10.
To use the doubles strategy, an example might be that students know 3 + 3 = 6, so they also know 30 + 30 = 60 (or 300 + 300 = 600)!
Addition Strategy Squad
Throughout this post, I’ve shown you some of my favorite strategies, and as students learn these strategies, I pull out these posters as a reference. We lovingly refer to them as the ADDITION STRATEGY SQUAD!
Finally, while you can of course teach these two-digit and three-digit addition strategies without these strategy people, I have tons of centers, posters, and printable practice pages you can use in your lessons if you need resources!
Want to read about subtraction strategies? Read about them in this post!