fractions / decimals

Milla · Post by **Milla** » Wed Feb 10, 2010 4:52 pm

my DS2 (y6) is safely into his super selective GS but ... although he can do on sight lots of the GS stuff his Y 8 bro struggles with (algebra, area, etc) he has an absolute blind spot wrt fractions into decimals and vice versa.
He got a level 5 SATS in the informal (terminology??) ones sat in Y5 but still wants to be able to crack them. I've tried pizzas. I've tried starting from the easy ones (1/4 = .25 etc) but he just doesn't "get" it. He's truly clever (honest!) but this is a blindness I just can't crack. It's particularly bad when it's one over something where he's keen to see the interesting number bit (aargh, by which I mean the 4 in 1/4) to end up as the point bit, thereby making 1/4 equal point four.)
Of course, normally, He Knows Best, but I think even he realises that he is on shaky ground here.
Anyone got the Open Sesame for me, whether "I did this ...." or "try this website..."
Many thanks.

stevew61 · Post by **stevew61** » Wed Feb 10, 2010 5:02 pm

Have you tried, I am sure you have, fraction and equivalence cubes?

Worked for my kids.

Very visual and hands on, saw them in a catalogue today, that arty crafty yellow moon one.

steve

Milla · Post by **Milla** » Wed Feb 10, 2010 5:13 pm

tell me more ...
(embarrassed to say that far from "have you tried, I am sure you have," I've actually never heard of

at least I think I haven't...)

WP · Post by WP » Wed Feb 10, 2010 5:17 pm

If he's OK with fractions in general and equivalences like 1/2 = 3/6, how about treating decimals as fractions where the denominator is 10, 100, etc? Maybe do percentages (i.e. fractions where the denominator is 100) first, i.e. 1/4 = 25/100 = 25% = 0.25.

Milla · Post by **Milla** » Wed Feb 10, 2010 5:23 pm

I think he leaps on too quickly and wrongly. So, because 1/4 = 25/100 = 25% he's too ready to think that everything is easily the percentage of what the number is. It's the shifting sands bit, the 2/3 being 66%. After a while I forget how to do the stages and am, I confess, a terrible teacher - I can "see" it, why can't he???
Can anyone suggest a good step-by-step book, a sort of CGS (or do I mean CPL???) for year 6. A sort of teacher at home thing??
Thanks, btw, for all help so far! much appreciated. it helps me think of the stages I'm not thinking of.

wonderwoman · Post by **wonderwoman** » Thu Feb 11, 2010 11:29 pm

Hi Milla

Fractions should be no problem if he always remembers to divide the numerator by the denominator.

So if he can do short division he's away.

To convert 2/3 to decimal he just needs to divide 2 by 3. To convert from decimals to fractions he just needs to know his columns - 10ths, 100ths, 1000ths etc and then convert by dividing both numerator and denominator by the largest common factor, eg 0.125 = 125/1000 = 1/8

Good luck

Milla · Post by **Milla** » Fri Feb 12, 2010 8:51 am

thank you, WW, I'll try that.

yoyo123 · Post by **yoyo123** » Fri Feb 12, 2010 10:12 am

as for websites try woodlands junior and BBC, some excellent games on there

BBC skillswise has some good factsheets and quizzes.

Fractions/decimals seem to be a stumbling block for lots of children (that and area/perimeter)