# Use and record a range of mental strategies to solve addition and subtraction problems involving two-digit numbers, including:the jump strategy on an empty number line, the split strategy, eg record how the answer to 37 + 45 was obtained using the split s

 1 Which number is 10 less than 16? 2 Changing Numbers: 48 to 47 3 Changing Numbers: 27 to 29 4 Changing Numbers: 68 to 58 5 Changing Numbers: 90 to 85 6 Changing Numbers: 66 to 76 7 Number Detectives: 10 + 27 = ? 8 Same or Different: Click all the boxes with the answer 25. 9 Same or Different: Click all the boxes with the answer 37. 10 Same or Different: Click all the boxes with the answer 34. 11 Same or Different: Click all the boxes with the answer 26. 12 The 20s zone: 22-2=?, 22-5=? 13 The 20s zone: 21-1=?, 21-7=? 14 The 20s zone: 23-3=?, 23-8=? 15 The 20s zone: 25-5=?, 25-8=? 16 The 20s zone: 26-6=?, 26-9=? 17 The 20s zone: 23-3=?, 20-6=? 18 The 20s zone: 24-4=?, 24-6=? 19 The 20s zone: 22-2=?, 22-8=? 20 The 20s zone: 23-3=?, 23-6=? 21 The 20s zone: 27-7=?, 27-9=? 22 Beyond 30 - 7 more than 39 23 Beyond 30 - 8 more than 35 24 Beyond 30 - 7 more than 37 25 Beyond 30 - 6 more than 38