1. Notice to Teachers Print this out to assist you with the lesson. This is an introduction chunking which is a strategy to add two or more two-digit numbers. It is a mental strategy but initially the students should write the numbers down. Slides 4 and 5 demonstrate the technique using markers. Click through the markers as you teach the concept. Slide 6 – 8 demonstrate the technique without markers. Slide 10 – 21 enable the students to short cut the written technique with the aim of making this a mental strategy. Slide 22 – 24 are speed exercises with a countdown in the bottom left hand corner. Speed and accuracy are the goals here. Good luck. Bob Brandis Not part of reliefteaching.com yet? Join and receive a free copy of 50 Ways to be a Better Relief Teacher as well as regular updates in eNews.reliefteaching.com

2. Chunking Mental Maths in Action

3. 46 + 37 40 + 6 30 + 7 40 + 30 6 + 7 7013 + + + 83

4. 58 + 36 50 + 8 30 + 6 50 + 30 8 + 6 8014 + + + 94

5. 30 20 39 27 +9 + 7 + + +50 16 66

6. 70 10 73 19 +3 + 9 + + +80 12 92

7. 70 10 74 15 +4 + 5 + + +80 9 89

8. 58 + 37 80+ 15 95

9. 46 + 35 70+ 11 81

10. 49 + 51 90+ 10 100

11. 48 + 39 70+ 17 87

12. 54 + 28 70+ 12 82

13. 59 + 34 80+ 13 93

14. 68 + 87 140+ 15 155

15. 35 + 79 100+ 14 114

16. 66 + 35 90+ 11 101

17. 35 + 76 100+ 11 111

18. 53 + 97 140+ 10 150

19. 56 + 68 110+ 14 124

20. 65 + 74 130+ 9 139

21. 605958575655545352515049484746454443424140393837363534333231302928272625242322212019181716151413121110987654321 STOP WORK 160+71690+88 214+88718+25 351+24842+63 493+89932+43 511+911085+70 Exercises 1172+461657+29 1233+211760+80 1376+151890+62 1467+561948+49 1596+20 22+90

22. 160+71 131 690+88178 214+88 102 718+2543 351+24 75 842+63105 493+89 182 932+4375 511+91 102 1085+70155 1172+461181657+2986 1233+21541760+80140 1376+15911890+62152 1467+561231948+4997 1596+201162022+90112

23. 605958575655545352515049484746454443424140393837363534333231302928272625242322212019181716151413121110987654321 STOP WORK 152+54678+22 261+60757+93 372+56817+95 475+36921+34 598+561095+36 Exercises 1116+421680+17 1254+251770+37 1329+251822+79 1497+471954+71 1547+802076+13

24. 152+54106678+22100 261+60121757+93150 372+56128817+95112 475+36108921+3455 598+561541095+36131 1116+42581680+1797 1254+25791770+37107 1329+25541822+79101 1497+471441954+71125 1547+801272076+1389

25. Not part of reliefteaching.com yet? Join and receive a free copy of 50 Ways to be a Better Relief Teacher as well as regular updates in eNews.reliefteaching.com