Here’s a quick and fun activity to introduce pairs that add to ten — important math facts to memorize early!  We used our Unifix cubes, but Duplos, Legos, or any other connecting blocks would work as well.

I made stacks of cubes for each of the numbers 1 through 9, including two stacks of 5, and I tossed them in a box.  I picked up the stack of 9 and asked my three-year-old how many more it needed to make 10.  He immediately guessed 1, so I had him pick up the single cube, add it to the 9, and re-count his new stack.

When he had decided confidently that 9 and 1 made ten, I challenged him to choose another group from the bin.  He picked a stack and counted it.  Then I had him lay it next to the group of ten and try to figure out how many more were needed.  He continued through all the numbers, matching groups to make tens and using his 9 + 1 group as a guide.

This was a very quick activity requiring almost no set up or clean up time, and it was just the right level of challenge for my little guy. A handful of times, he had to stop, re-evaluate, and adjust his choice, but he kept at it and enjoyed it.

If you don’t have Unifix cubes, I recommend getting some.  They are useful for a million different activities!  Click the link below to check them out on Amazon.