Halves and doubles

[ggglimpopo]

My ds has to learn the halves and doubles up to 20. I first of all tried with mung beans (ok, you have four beans, take away half and how many do you have? Reply - 6?). Then we tried with an apple but once you take the apple away, so he is not actually counting, he just starts guessing and saying "but how do you KNOW?" as though the numbers are magic. Have tried the mummy dividing a cake drawing, and again, he is ok counting once you have divided, but on the division thing he has no idea, ditto doubling. He just doesn't get it. Short of teaching him his two times table and then teaching him to apply it to his homework of halves and doubles, does anyone have any ideas. And at teacher for expecting him to pick this up in an evening.....and learn it all off pat. French schools.....grrrrrrrrrrrrrrrrrrrrrrrrr. Sod all for three years, then PhD level in three terms. Well, nearly!

[Twiglett]

if you have 4 mung beans and take away half you'll have 3 and a half and be a big fat hippy to boot

[Twiglett]

do it with chocolate?

here's 1 choc if I double it how many will you have

mummy has 2 chocs if I give you half how many will you have

every time he gets it wrong YOU eat the choc

[popsycal]

the best way to get little ones to understand halves IMO

get a bar of chocoalte - mars bar or whatever
tell him to half it but you get to choose which half...
after a few goes you can be sure that he will make the 'halves' as equal as possible:)

[ggglimpopo]

Bloody good idea the chocolate. Will try it. Now going to start thread on tribulations with dd2.

[singersgirl]

DS2 likes to double and half raisins. Same principle - if he gets it right, he gets to eat them. We use them for number bonds too sometimes.

[singersgirl]

Well, of course, not individual raisins.....

[Feistybird]

what are number bonds?

[popsycal]

19+1=20, 18+2= 20
etc

[Feistybird]

aaahhhhhh cheers popsy

[notagrannyyet]

Do'nt quite understand this. Is this some fancy way of learning the 2 times table? If it is then you could buy one of those singy -songy tape things for car journeys, Drives you round the twist but all mine learnt their tables this way.

[JanH]

lol @



You mean numbers aren't magic???

[JanH]

Anyway, why not do 2 times table? Do they not do tables in France? Why not? They are bloody useful forever!

[popsycal]

a good one for halving the bigger number....say half 16.....

just learn halves up to 10

then for 16 - you havlf the 10 (5) theb the 6(3)
add em up = 8
(posh word id partitioning :)_

[popsycal]

agree learn the 2 times table too