Home > #MTBoS, A Level, Maths, Resources, Teaching > Grid Method Matrix Multiplication

## Grid Method Matrix Multiplication

This week I was “tweeted” at by one of my “followers” (@bt2bn) with the “hashtag” #MTBOS. I thought, “I wonder what that stands for?” and promptly looked it up. It stands for “Math(s) Twitter BlogO Sphere” and I thought “that sounds like something I’d be into.” So I signed up. (Sorry for the unworldly amount of quotation marks in that opening stanza…)

On further inspection, the #MTBoS seems to be a maths based #blogsync. This week’s prompt was to choose a tweet you’ve favourited and write about it. And this tweet arrived in my feed today and fits the bill entirely.

I retweeted this, and it turns out that quite a few people did already know about it and teach it this way. I’ve never encountered this method before, but given that the preferred multiplication  method for most of my pupils is the grid method, it would seem to make sense to offer this as an option next time it comes up.

I was intrigued to see this new method, and I was also intrigued to know so many were using it. If you do, I’d be interested to here your views, and if there are any draw backs. I’ve got a while before it comes up this year, so I’m going to play around with it and get a real feel for any positive or negative points, and to see which method I feel is better for understanding.–

1. October 19, 2013 at 2:17 am

I saw the same post and was also intrigued. I don’t teach matrix multiplication but I do teach polynomial multiplication and this method looks like it would work for that too. I am new to Twitter and the whole MTBoS but one thing I am loving is all the sharing!

• October 19, 2013 at 8:42 am

Hi Heidi, thanks fir the comment. I have used it with polynomials before, and it does work Well.

2. October 19, 2013 at 6:26 am

I’ve never seen that before either – I’m not teaching any matrices this year so I’ll come back next year to remind myself of this!

3. October 20, 2013 at 12:16 am

We just finished our matrices unit and I used this method for multiplying matrices. Students seemed to work well with the organizer. I have a stack of papers to grade and then I’ll know for sure how well it worked. We spent 2 block days on working matrices by hand, 1 block day on using the calculator, and 1 day of review. Students took 2 tests – a non-calc and a calc test … each of the tests were just 5 problems. I described some of our lessons briefly at http://algebrasfriend.blogspot.com/ and on my 180 blog: http://180snaps.blogspot.com/

1. November 28, 2013 at 5:27 pm