Addition with Regrouping – Printable LEGO® Math Activity!

If you’re like me, teaching addition with regrouping (and subtraction with borrowing) is not on the list of favorite things to do! It can be a hard concept for kids to understand. I highly recommend starting with a firm understanding of place value and then introducing the concept of regrouping with the help of manipulatives. Here’s where the LEGO® bricks come in! Pull out the LEGO® tub, and it hardly feels like work at all!

I used this activity to successfully introduce addition with regrouping to my first grader last week. He even enjoyed it! His math curriculum introduces carrying late in the year and then comes back to it in second grade.

Here’s how to teach addition with regrouping (carrying) with LEGO® bricks.

First, you’ll want to print the activity pages and addition problem cards. Well, read this post first, and then print them! The link to print is at the bottom of this post.

I recommend laminating the two activity pages. Kids can write with a dry erase marker and use the pages again and again. Another option is to slide them into clear page protectors.

You’ll need about fifty 2 x 2 square LEGO® bricks.

Explore – how will the student approach the problem?

Before we got started, I gave Jonathan some paper and asked him to solve 25 + 17. He added 5 and 7 and got 12, and then paused for a minute. He wrote down 12 in the ones column, sort of. Then he added 2 + 1 and got 3. So his answer was 312. We built 25 and 17 with LEGO® bricks, and that was clearly not anywhere close to 312! He counted them and found that the answer should be 42. Then we were ready to learn about regrouping!

Step 1: Choose an addition problem card. Build the problem in 10’s and 1’s.

Step 2: Add the ones together and move them over to the solution page.

Step 3: Think – are there more than 9 ones? If there are more than 9 ones, we’ll need to move 10 of them over to the tens column. We can’t write 10 (or 11, 12, etc.) in the ones column because each column must be only one digit. So we need to regroup.

Pull out 10 ones and build a group of 10. Move it over to the tens column.

Step 4: Add the rest of the tens. How many tens are there altogether? How many ones are left in the ones column?

I included spaces to record the problem both horizontally and vertically. I wanted my son to understand that both formats mean the same thing. Also, I wanted him to practice carrying the ten that we regrouped to the tens column.

See, math isn’t so bad after all!

This file is free to print for email subscribers. Don’t worry if you have already subscribed. You can go ahead and enter your name again to print the mats, and you WON’T be added twice.

Find more hands-on math inspiration!

1. ##### Glyndis Dec 1, 2019

Thank you so much for this idea! My son is struggling in school and I needed some fresh, hands-on ideas for him!!

2. ##### Charmaine Shabalala Sep 5, 2021

Appreciate the help!