Hi bigbutsrus1
I have so been there and absolutely feel for you.
First off you have to recognise this is stressing you out and even with the best will in the world to avoid sending negative messages about maths to your child - you probably already are signalling issues with math and worry.
You also said that you had a negative exprience with maths in primary.
So my advice, because I was at a point of total despair, is to take advantage of the era we live in where many clever people have expended all sorts of energy on making maths more entertaining and trying to explain concepts in a more understandable, and frankly, fun way.
My advice is support the maths learning but hand it over to someone/ something else - like an on-line tutorial.
I say this because I sincerely feel that practice and exposure to more maths makes doing maths in class easier. If the school isn't given your DD the support (and it sounds like there are issues there) then please don't feel there are no other solutions:
WORKBOOKS:
Go to any large newsagent or bookshop and have a look at the wide range of KS1 maths workbooks available. I suggest you let your DD look through and chose one that suits (she may respond better to more visual books with addition/ subtraction/ etc... explained pictorially).
FREE on-line resources:
Woodlands Junior School Maths Zone - all I can say is absolutely fabulous website with links to all sorts of resources (primarily games) in whatever area of maths you feel your DC needs more practice in - link here: resources.woodlands-junior.kent.sch.uk/maths/
Cool Maths for Kids: www.coolmath4kids.com/ - it's not the easiest website to navigate - but there are all sorts of games & resources/ explanation on how to do things. It's worth spending some time and exploring - or using the search facility - there usually is something to help with a concept.
TUTPUP: www.tutpup.com/ - more maths games & ability to control difficulty.
BBC Bitesize KS1 Maths: www.bbc.co.uk/bitesize/ks1/maths/ - games to practice key concepts tested in KS1 SATs - can control difficulty of games.
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now with DD1, she left KS1 with a NC 1 in Maths on KS1 SATs and had absolutely no confidence in her ability to do maths. I used to get upset trying to explain how to take 1 from 10 and she'd reassure me that 'It's o.k. Mum, Mrs. X says I'm just no good at maths' - completely accepting that this is just something she'd never do. (Which drove me mad - to be honest!)
So we turned to mathsfactor (an on-line tutorial in maths presented by Carol Vorderman).
I have to say that others here on mumsnet have sung the praises of:
komodomaths: komodomath.com/
Maths Whizz: www.whizz.com/
and Mathletics: www.mathletics.co.uk/
Our choice was mathsfactor: www.themathsfactor.com/ - this was consciously because it was presented by a woman. I definitely wanted me girls to see that girls can be good at maths. Carol Vorderman begins each lesson with a video tutorial briefly presented a key concept, you then have a little warm-up quiz or a game and then the main practice. This amounted to no more than 1 1/2 hours of extra maths (5 sessions) a week - and the timing was totally flexible and suited our hectic family life.
All of these on-line tutorials, not just mathsfactor, I've mentioned will assess your child at where they're start from where they're at. Each offers building block progression working through concepts gradually with lots of video game style practice (which is much more appealing to this generation of children).
Right now mathsfactor is offering a winter maths club for about £5 which will last all December and into January - so for very little outlay you can have a long trial of this programme and all of these programmes usually offer a period of free trial (usually a month) - again meaning that you can try things out and decide what is best for you with very little outlay.
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I should add there there is finally one further free maths tutorial - which is that you can work through maths lessons/ practice with Khan Academy: www.khanacademy.org/math/cc-third-grade-math - but this presumes a starting level of ability to add and subtract 2 digit numbers and this may be beyond what your DD can do just now.
However it is useful to know that another form of explanation on how to do things (which is also visual) is available (for future reference at the very least).
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Having been through this scenario myself and come out the other side (DD1 who scored NC L1 KS1 SATs is now being put forward for L6 paper at KS2 SATs) - I can genuinely say that these days there are so many resources out there that you don't have to be expert - you just have to decide what suits your budget, your child's learning style and interest and how much you're personally willing to be involved. I had to do a lot of data entry at first, because both DDs started young (6 for DD1 and 5 for DD2, who got jealous of DD1 having fun on mathsfactor and begged to join for her birthday present).
For us it meant that the key concepts were being learned. The pace ultimately was faster than our school (although the multiplication package in the arithmetic school seemed to go on for a long while - it paid off, because times table facts were so secure division and work with fractions seemed a doddle).
The only drawback I can see with mathsfactor is it really avoids anything to do with geometry - so that side of things will have to be covered in school & elsewhere (workbooks/ websites). But those core skills: addition/ subtraction/ multiplication/ division & their application with concepts like percentages, fractions, proportions are thoroughly covered by mathsfactor.
Everyone is different. You may not want to go down this road - which I totally respect. But, I just thought I should say that there is help out there and to encourage you to have a look at what's on offer (and I'm sure there's even more now) and try things out. There is a solution out there for you.