# 20min lesson on multiplication facts and division

Discussion in 'Primary' started by Teacher1974, Mar 16, 2012.

1. ### Teacher1974

Triangles work well for linking mutliplication with division.
I can't do triangles on here well but you put the answer at the top (e.g. 56) and the two numbers that you multiply together at the bottom (e.g. 7 and 8).
56
<u>/ \</u>
7 8
The children can tell you or write the related sums on whiteboards e.g. 7 x 8 = 56. 8 x 7 = 56. 56 / 7 = 8. 56 / 8 = 7.
You can then make it harder by giving them two of the numbers and asking them to find the third. You could multiply one of the numbers by 10 and see if they can work out the others. You could double one of the numbers and see if they can work out the others. There are lots of ways you could extend this for Y5, even going up to TU x TU for the most able.
Good luck!

2. ### LGR22

Use counters to make arrays. Make an array of 3 x 5. This demonstrates that 5 x 3 = 15 and 3 x 5 = 15. It easily follows that 15 / 3 = 5 and 15 / 5 = 3. This is really visual and hands on.
Make sure you have the right language: 5 x 3 is five, three times, 3 x 5 is three, five times.
If you then change the counters for 100 squares, and then reduce the 100 squares to strips of 10s, this demonstrates 0.5 x 3 = 1.5 or 0.3 x 5 = 1.5. You then can use visualisation to make it 10 times, 100 times, 1000 times bigger or smaller.

3. ### LGR22

They're not sums, they're products.

4. ### minnieminxNew commenter

Except for the division ones which are quotients!

5. ### Teacher1974

Whatever. You know what I mean. Christ - try to help someone and get shot down in flames. For the love of God get a grip. It's Friday night.

6. ### LGR22

Yeah I know! I thought about it, and thought again, but I've got a pedantic streak with maths language. I couldn't help myself. Maybe I ought to have another beer and stop looking at this site on a Friday night. No offence intended.

7. ### minnieminxNew commenter

But when it is Friday night I have a drink or three and so become even more argumentative than usual!

Though I've seen two trainees in the last month use the term 'sum' in a maths lesson incorrectly, so I am also trying to stop the same thing happen for the OP.
(And show off to the person who corrected you to point out that they were also wrong!) I am horrible really!

8. ### LGR22

Didn't spot that...b****r. Ok cleverclogs, they're quotients...whatever!

9. ### pottyparrot

Eh hem... You are meant to be giving me advice not arguing lol!

Only joking- thanks for the ideas quite like the triangle one! So what do I say to the children instead of sums "write down the related...."? X

10. ### minnieminxNew commenter

number sentence

See Saturday morning and I'm much more helpful!

11. ### pottyparrot

Haha ... I know not to post on a Friday night from now on! Xx