It's hard to believe just how useful halving and doubling can be for a mathematician but trust me, it's is so good to be able recall these facts quickly.
Brie-Anna de Mouse, Star of Maths with a Mouse
DOUBLING & HALVING KIRFs
DH1 Derive doubles of whole numbers to 15, corresponding halves
DH2: Near doubles addition
DH3: Derive doubles of whole numbers to 50, corresponding halves
DH4: Double or halve any whole number to 100
ACTIVITY TIME
Take aim...fire! It's time to play Archery Doubles from ictgames.com
With three levels of challenge, this is a great starting point for practising doubling.
Level One: Doubles up to 10 + 10.
Level Two: Double multiples of 10 up to 100 + 100.
Level Three: Double any number up to 109
Nobody wants a bear with a sore head, a mouse with a tummy ache or a dinosaur with toothache. In Dinosaur Dentist (another great activity from ictgames.com), you will need to use your near doubles skills.
How?
Well, if you know double 2, you can simply add on one to find 2+3.
If you know double 7, you can simply add on one to find 7+8.
Alternativiely, if you know double 8, you can simply subtract one to find 7+8 .
For all your specific halving and doubling practise at speed, look no further than the class maths game that is Hit the Button. Wow! Just look at all those great choices below! Thanks Topmarks - top marks for you! A++++
Topmarks does it again! With Loop Cards for lots of different skills, this is even better! Why? With each set of loop cards, you can either find the double or work backwards by halving! It's double the fun!
I love a Quizzy Whizzy - have you seen my Quizzy Whizzy section?
It seems Transum loves a Quiz too! This is a little more challenging as it involves decinals but if you have great doubling skills already, you will be a boss in Doubling Quiz.
Logic Double Cards from mathplayground.com is a fun way to use some of your doubling skills but is also a fun way to realise that you have spent quite a long time trying to beat your high score! Can be rather addictive - you have been warned!
Looking for more ways to practise recalling your knowledge? click on Pick Your Skill. Check out my guide to see which games have options for the skills that you want to practise!
