2. Today we will be learning: different ways of making totals using odd and even numbers to investigate a general statement.

3. Mental Activity We are going to practise adding numbers quickly.

4. Top Tips An odd number added to an odd number gives an even number. Two even numbers added together give an even number. An odd number added to an even number gives an odd number.

5. Think about whether each answer will be odd or even before you work out the answer to these. 12 + 1311 + 1514 + 1231 + 3221 + 3532 + 26

6. Think about whether each answer will be odd or even before you work out the answer to these. 13 + 1325 + 2515 + 1611 + 1451 + 5255 + 45

7. Main Activity Today we are going to investigate using odd and even numbers. How many totals under 30 can you make using only two odd numbers? How could you start this investigation?

8. You could start with the smallest numbers and work upwards. 1 + 3 = 4 3 + 5 = 8 5 + 7 = 12 Can you see a pattern in how the numbers are growing in each column? What will the next two pairs of numbers be? 7 + 9 = 16 9 + 11 = 20

9. Can you predict what the highest total under 40 will be? How will you make sure you have added every possible pair of odd numbers and not missed any out? Top Tip Once you have spotted a pattern, you can use it to check for mistakes.

10. Group Work Explore different ways of making totals up to 30 using two odd numbers. Then do the same using two even numbers. Explore different ways of making totals up to 20 using two even numbers. Explore different ways of making totals up to 30 using three odd numbers. Then do the same using three even numbers.