Add tens first, then ones
24 + 13 means 2 tens and 4 ones plus 1 ten and 3 ones.
First combine the tens: 20 + 10 = 30. Then combine the ones: 4 + 3 = 7. So 24 + 13 = 37.
Year 2
Add tens and ones using unit cubes and tens rods
Use tens rods and unit cubes to combine tens and ones before moving to more formal written methods.
Lesson overview
Number - addition and subtraction
When we add a number, we can look carefully at how many tens and how many ones there are. Tens rods help us see groups of ten and unit cubes help us count the ones. This makes it easier to combine the parts of each number in a calm, visual way.
A ones total can still stay under ten
32 + 15 means 3 tens and 2 ones plus 1 ten and 5 ones.
The tens make 40 and the ones make 7, so the whole answer is 47.
Add tens to tens and ones to ones
41 + 6 keeps the tens the same and adds more ones.
41 has 4 tens and 1 one. Adding 6 ones makes 7 ones, so the answer is 47.
Worked example
Work out 26 + 12 using tens rods and unit cubes.
- Look at the first number. 26 is 2 tens and 6 ones.
- Look at the second number. 12 is 1 ten and 2 ones.
- Add the tens: 2 tens plus 1 ten makes 3 tens.
- Add the ones: 6 ones plus 2 ones makes 8 ones.
- 3 tens and 8 ones make 38.
Try it
Look at the rods and cubes, then choose the answer that matches the calculation.
Question 1
Question 2
Question 3
Question 4
Question 5
Common mistakes
These are easy slips to watch for when using rods and cubes.
- Mixing tens and ones together instead of adding tens with tens and ones with ones.
- Counting a tens rod as 1 instead of 10.
- Rushing to a column method before understanding what the blocks are showing.
Related topics
These ideas support visual addition and place-value understanding.
- Recognise the place value of each digit in a two-digit number.
- Add and subtract numbers using concrete objects, pictorial representations, and mentally.
- Add and subtract numbers using concrete objects and pictorial representations, including two two-digit numbers.