# Teaching my son the multiplication tables **URL:** \ **Category:** Mental Calculation, Mathematics, and Puzzles\ **Created:** [December 21, 2020, 7:09am UTC](https://forum.artofmemory.com/t/teaching-my-son-the-multiplication-tables/58085 "2020-12-21T07:09:05Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![Kinma](https://forum.artofmemory.com/letter_avatar_proxy/v4/letter/k/a88e4f/32.png) [@Kinma](https://forum.artofmemory.com/u/Kinma)\ **Post date:** [December 21, 2020, 7:09am UTC](https://forum.artofmemory.com/t/teaching-my-son-the-multiplication-tables/58085/1 "2020-12-21T07:09:05Z")
I am teaching my son the multiplication tables in a Trachtenberg kind of way. The tables until 6 are easy for him. We are now training to do 8-12. 7 is the most difficult for him (as it is for many kids). We have already done ‘sequences’ for about two years. I started doing those from when they were 3-4 years old. A sequence is 2, 4, 6, 8, … Or 3, 6, 9, 12, … Or 7, 14, 21,… etc. My youngest is 5 and with her I only do the sequences. My oldest is now learning the tables at school. What I do for numbers close to 10 (8 - 12) is this. I have him first add a zero to the number (multiplication by 10) and then add or subtract the number or twice the number. 11 = 10 + 1, so: 1 \* 11 = 10 + 1 = 11 2 \* 11 = 20 + 2 = 22 3 \* 11 = 30 + 3 = 33 4 \* 11 = 40 + 4 = 44 5 \* 11 = 50 + 5 = 55 6 \* 11 = 60 + 6 = 66 7 \* 11 = 70 + 7 = 77 8 \* 11 = 80 + 8 = 88 9 \* 11 = 90 + 9 = 99 10 \* 11 = 100 + 10 = 110 11 \* 11 = 110 + 11 = 121 12 \* 11 = 120 + 12 = 132 9 = 10 - 1, so: 1 \* 9 = 10 - 1 = 9 2 \* 9 = 20 - 2 = 18 3 \* 9 = 30 - 3 = 27 4 \* 9 = 40 - 4 = 36 5 \* 9 = 50 - 5 = 45 6 \* 9 = 60 - 6 = 54 7 \* 9 = 70 - 7 = 63 8 \* 9 = 80 - 8 = 72 9 \* 9 = 90 - 9 = 81 10 \* 9 = 100 - 10 = 90 11 \* 9 = 110 - 11 = 99 12 \* 9 = 120 - 12 = 108 12 = 10 + 2, so: 1 \* 12 = 10 + 2 = 12 2 \* 12 = 20 + 4 = 24 3 \* 12 = 30 + 6 = 36 4 \* 12 = 40 + 8 = 48 5 \* 12 = 50 + 10 = 60 6 \* 12 = 60 + 12 = 72 7 \* 12 = 70 + 14 = 84 8 \* 12 = 80 + 16 = 96 9 \* 12 = 90 + 18 = 108 10 \* 12 = 100 + 20 = 120 11 \* 12 = 110 + 22 = 132 12 \* 12 = 120 + 24 = 144 8 = 10 - 2, so: 1 \* 8 = 10 - 2 = 8 2 \* 8 = 20 - 4 = 16 3 \* 8 = 30 - 6 = 24 4 \* 8 = 40 - 8 = 32 5 \* 8 = 50 - 10 = 40 6 \* 8 = 60 - 12 = 48 7 \* 8 = 70 - 14 = 56 8 \* 8 = 80 - 16 = 64 9 \* 8 = 90 - 18 = 72 10 \* 8 = 100 - 20 = 80 11 \* 8 = 110 - 22 = 88 12 \* 8 = 120 - 24 = 96 We have not yet done a lot with the 7 table. We do the 7 sequence from time to time. For the table I plan to use the following. He is quick to halve. 7 is 5 + 2. 5 is halve of ten and 2 is double of one. So I call it ’ halve and double’. There is a shift between halve and double, but ‘halve and double’ just sounds better. In the case of 4 (times 7), we do halve of 4 (2) and double 4 (8). I have him picture the 2 next to the 8 to form 28. In the case of 8, again we do halve of 8 (4) and double (16). He knows by then he needs to concatenate them, effectively picturing 4|16 = 56. Or he can just do 40+16. Btw, I don’t force him to do anything. I just show him options. Until now he just picks them up easily. For even numbers ‘halve plus double’ is easy: 2 \* 7 = 1|4 = 14 4 \* 7 = 2|8 = 28 6 \* 7 = 3|12 = 42 8 \* 7 = 4|16 = 56 10 \* 7 = 5|20 = 70 12 \* 7 = 6|24 = 84 For odd numbers I just have him get the next number in the sequence. Either that or have him multiply the number by 10, halve and then double: 1 \* 7 = 5 + 2 = 7 2 \* 7 = 10 + 4 = 14 3 \* 7 = 15 + 6 = 21 4 \* 7 = 20 + 8 = 28 5 \* 7 = 25 + 10 = 35 6 \* 7 = 30 + 12 = 42 7 \* 7 = 35 + 14 = 49 8 \* 7 = 40 + 16 = 56 9 \* 7 = 45 + 18 = 63 10 \* 7 = 50 + 20 = 70 11 \* 7 = 55 + 22 = 77 12 \* 7 = 60 + 24 = 84 ---
**Author:** ![Josh](https://forum.artofmemory.com/user_avatar/forum.artofmemory.com/josh/32/21_2.png) [@Josh](https://forum.artofmemory.com/u/Josh)\ **Post date:** [December 30, 2020, 7:06pm UTC](https://forum.artofmemory.com/t/teaching-my-son-the-multiplication-tables/58085/2 "2020-12-30T19:06:55Z")
8 posts were split to a new topic: [Trachtenberg and Arthur Benjamin Method](https://forum.artofmemory.com/t/trachtenberg-and-arthur-benjamin-method/58364) ---
**Author:** ![MalcolmHyndman](https://forum.artofmemory.com/letter_avatar_proxy/v4/letter/m/f1d935/32.png) [@MalcolmHyndman](https://forum.artofmemory.com/u/MalcolmHyndman)\ **Post date:** [December 31, 2020, 7:35am UTC](https://forum.artofmemory.com/t/teaching-my-son-the-multiplication-tables/58085/3 "2020-12-31T07:35:23Z")
I like this. I also taught both my sons, 6 and 7, their tables when they were 5 and 6. I used the Major system and they learned them over about a month. They have no problems with recall. eg. 12 x9 = Tune Up using Adhesive = 108. easy peasy…