The most recent sets of mental arithmetic questions have now been published for years 4, 5 and 6.
For year 4 it is very much about multiplication and division, including some of the easier rules of divisibility eg a number is divisible by five if the units are five or zero.
The year 5 sets of questions concentrate on knowing times tables as well as being able to use this knowledge to answer further questions. There is one very tricky question here:
what is 28 x 3?
One way to do this is to double 28, making 56 and then add on another 28 to make buy cheap ambien overnight 84.
The year 6 sets include multiples, square numbers and prime numbers. By the end of year 6 children should know at least the first 10 square numbers (eg 4 x 4 = 16) and be able to recognise small prime numbers.