Tuesday, 5 March 2013

Bridging Through 10 - KS1 Maths - Subtraction

It's not all bad... but can I just say, in the interests of solidarity with other home schooling parents whose children are, at times, uncooperative, shouty and downright badly behaved... we had an awful, write-off morning. We all fell out. I considered leaving home, or at least selling one or two of them. Especially the bossy, stroppy one... We didn't get anything (much) done and I really felt like sending her back to school. There were time-outs and A Serious Conversation. I walked away from the violin battle but, amazingly, Francesca finished the practise, unaccompanied.

After lunch, it all got better. Elizabeth and Sebastian were engrossed in a make-believe situation which, I later discovered, seemed to involve emptying the wardrobe and scattering everything all over the floor, but never mind, I was sooo pleased that they were happily cooperating and out of the way(!) Francesca and I finally cracked the 'bridging through 10' thing that she has, thus far, avoided understanding. I say 'avoided' because I've tried to explain it to her before, when it had come up in her various maths workbooks. She usually shouts me down and says she KNOWS how to do it and then counts on her fingers and messes it up. Anyway...

How I Finally Got The Bridging To 10 Message Across

Having no multi-link cubes (as pictured in the Heinneman maths book) we used Duplo for this task.

The aim was to use 10 as a 'bridge' in the process of subtracting single digit numbers from 2 digit numbers. We started with fairly simple sums such as 12-6 and 13-7.

The 'bridge' idea is a method for going via 10 and then using the (hopefully) familiar number-bonds to 10 to make the sum easier. Francesca has learnt her number bonds to 10, so she is quite confident in recalling that 1+9=10, 2+8=10 and 3+7=10 etc.

SO, for the sum 15-9, she used Duplo to represent '15' by making a stack of 10 bricks (one ten) and having five loose bricks (five units). Then, to subtract 9, she first took away the five units, to get to ten, then worked out she needed to take away four more, from the remaining ten. Knowing that four goes with six, to make 10, she could deduce the answer quite simply.

I had her build with the blocks for every sum, in each case taking away the spare units (that weren't part of the 10 stack) then taking away the rest from 10. And she Got It! Yey! She really listened to me. She really tried to do what I was asking. She was willing to talk me through her method as she did the sums, until I knew she understood.

Actually, this was after she had shouted at me this morning and tried to do the same sums with her number line, getting about half of them wrong. This gave me good grounds to insist that, this time, she really try to take on board what I was explaining. I sat with her and worked through the ones that had been wrong, then helped her to do another page. I think she was pleased with herself, in the end. Perhaps she'll believe me next time I say I've got a good method that's different to her own(!)

In Other News

We finally did some IT. Francesca heard her daddy talking about Excel and decided that she wanted to learn about that too. My mum and dad have made her an Excel-style grid, on paper, to work with to help her understand how the cells are labelled: A3, B5 etc.

Here she is 'cracking the code':

Her grid comes with a set of coordinates. When she colours in the correct cells, she will see something revealed (actually, it's going to be an F but she doesn't know that yet).

I'm pleased (again) with her organisational skills. She said, "I want to give it a title," and immediately ruled a line on which to write "Crack The Code."

Then, instead of colouring in as she goes along, she is writing the coordinates in the correct cells, to colour in all at once at the end. She's also circling the ones that she has done, so she knows where she's up to. I'm impressed!

Sebastian's been honing his cutting skills:

Elizabeth's been keenly doing more maths - two pages of her book, which is bringing her on to simple addition.

She did some of her English book, too, writing the letters 'ck' and 'qu' in the right places.

Francesca didn't do English as such, but she did some writing for History. We've started the long-awaited time line:

It runs from Francesca's birth to the present day, with a selection of photos of key events during that time. She's writing a sentence or two to go with each photo. I'm hoping to develop the idea, perhaps adding more past events or introducing things that happened prior to her birth. We'll zoom out a bit, to a larger scale, and do events from my lifetime (perhaps) and then zoom out again to do events in our house's lifetime (c100 years) etc. I'm excited to have finally got started with this project.

And finally... We played outside today, with neighbours, after school. It was cold enough for coats and gloves but dry and pleasant enough to get the toys out/use the scooters/ride the tractor/use the slide. Roll on summer!

1 comment:

  1. Glossing over the morning.....the timeline looks very smart and clear. I like the angle that you are approaching it from.