Here are some activities you can try to help you with doubling and halving.
(The first 2 two sites are a bit noisy! You might want to turn the sound off after a few goes!) They are quick activities and good for if you need practise with doubling smaller numbers.
Doubling numbers up to 10
Doubling numbers beyond 20
The following activity will help explain a strategy for doubling slightly bigger numbers.
If you are confident at doubling bigger numbers you can try Top Marks Hit The Button. Choose the doubling option, then the level you want to try, but you could also try doubling some decimal numbers!
If you need a little more help doubling bigger numbers the following activity will also explain a strategy to help you.
Again Top Marks Hit The Button is a useful way to practise halving numbers. There are lots of different levels so you can choose one that will suit you. See if you can work towards trying the next level.
You can use the loop cards in this link to help you with doubling and halving. Choose the level you want to practise, but remember to try and challenge yourself by trying the next set up!