Hello there:
First off my advice is look into the new national curriculum programme of study for maths: www.gov.uk/government/publications/national-curriculum-in-england-mathematics-programmes-of-study - scroll down and click the programme for KS1 & KS2. Year 1/ 2 = KS1 and Years 3 - 6 = KS2.
So this document will tell you broadly what should be covered by year and therefore can help you to gauge the kind of things your child should be learning to do during a given school year.
So for Year 1 - the statutory requirements are:
Statutory requirements for Y1 (page 6 of KS1/ 2 programme of study)
Pupils should be taught to:
? count to and across 100, forwards and backwards, beginning with 0 or 1, or from any given number
? count, read and write numbers to 100 in numerals; count in multiples of twos, fives and tens
? given a number, identify one more and one less
? identify and represent numbers using objects and pictorial representations including the number line, and use the language of: equal to, more than, less than (fewer), most, least
? read and write numbers from 1 to 20 in numerals and words
Things you can do for free on-line to help:
First off can I introduce you to ICT Games: www.ictgames.com/counting.htm - I've put in 'counting games' and would highly recommend bead string (numbers to 10 or 20) and later abacus (so understanding place value that the 1 in 13 represents 1 ten and the 3 represents 3 units).
the wonderful Woodlands Junior School Maths Zone: resources.woodlands-junior.kent.sch.uk/maths/ - a lot of the skills for KS1 can be practiced as games under 'NUMBER SKILLS' section. - there are some lovely 100 square number games on this website as well: resources.woodlands-junior.kent.sch.uk/maths/interactive/numbers.htm - in fact a lot of games on this number skills page are really useful for early maths skills practicing.
Math Champs: www.mathschamps.co.uk/#home - has free games organised by age bands 5-7, 7 - 9 and 9 - 11.
Cool Maths 4 Kids www.coolmath-games.com/1-number-games-01.html - has some lovely number games as well (again free).
With all these games - I find it is useful to try them out first yourself and gauge whether they're too complicated or stressful for your child. However, I have sometimes been very surprised what my DDs have taken to.
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Now for KS1 there are a ton of early maths workbooks. You literally can go to any newsagent or book shop and see a wide selection. My advice is take your DC along and let them guide you what to chose. Some children prefer proper numbers (DD2) and others prefer to learn these early concepts visually (DD1).
If your school subscribes to My Maths or Education City - there are all sorts of games you can play any time on these - so find out your child's username/ password and encourage them to play for 5 - 10 minutes whilst you make dinner/ etc...
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Ordinary things about home you can do:
Snakes & Ladders is brilliant - you can start with just counting on (so addition) but gradually encourage your child to count on in jumps - maybe jumps of 2 (if even) or 2s and then 1 (if odds). You can work on subtraction by playing it backwards.
Once your DC is ready for numbers >6 - just add another die - 2 dice = 12, 3 dice = 18, 4 dice = 24 - the game goes a lot faster (which can be a good thing) but you can always play it forward and backward again to make it go faster.
When it comes to learning times tables - you can use the dice to help. So you can declare you are paying snakes and ladders for x2 and use 2 dice - then each roll is what you multiply 2 by - so for example if you roll a 4 it's 4 x 2 = 8 (move forward 8).
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SNAP
Just use an ordinary deck of cards. Pick a starting number - so maybe '6' - write it down on a sheet of paper or a post-it. Shuffle deck. Ace = 1, 2 - 9 as numbered and Jack/ Queen/ King all = 10. Flip a card - say it's a '4' - what is 6 + 4. It's 10. It may take counting on fingers at first - but it all works toward being able to add mentally.
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NUMBER BONDS
Schools really overkill on learning all number bonds 'for' 10 - 1+9/ 2+8/ 3+7/ 4+6/ 5+5/ 6+4/ 7 + 3/ 8 + 2/ 9 +1 - of course also 10 + 0 & 0 + 10. BUT I really think it is important to learn them for numbers 5 - 9 as well (