Children should do Sudoku and crosswords in school to boost their brain power, experts say.
Doing Sudoku puzzles improves memory and doing crosswords improves verbal fluency and word games are great for learning vocabulary, University of Cambridge researchers have found.
Their report, Puzzles in Education, presents the results of an extensive review into the use of puzzles in schools.
Although 75 per cent of teachers use puzzles in some form in their lessons, they are often seen as ways to engage children rather than improve learning.
But the research suggests that puzzles have far wider psychological and cognitive benefits for pupils including those at the Key Stage Two level, aged seven to 11 years old.
The games were found to be most useful in learning terminology and vocabulary, abstract reasoning and memorising data.
Sudoku, the popular Japanese logic-based puzzle, is especially useful in teaching maths and science, if it is adapted. 
For instance, using chemical symbols instead of numbers.
Nursery school age children are being taught internet safety because of the soaring use of iPads and tablets.
About 28 per cent of three-and four-year-olds use a tablet computer at home, according to Ofcom, and many nurseries have iPads for children.
The charity ChildNet, which helps schools hold classes on the web, said it is increasingly being invited in to pre-school establishments to hold online safety lessons. 
The toddlers are given simple messages not taught about specific dangers, such as online bullying or the risks of being groomed.
‘This is the age where children are starting to interact with technology,’ said chief executive Will Gardner.
‘The message is: If something goes wrong, tell someone.
‘Touch screens have enabled access to technology to go right down the age range.’
Word searches are recommended for learning about specific topics, particularly where a knowledge of terminology or vocabulary is needed.
And crosswords help verbal fluency, improve memory and general problem-solving skills. Generally, all puzzles were found to support the National Curriculum. 
The study, compiled by the university’s Faculty of Education, was commissioned by Puzzler Media.
‘This research reveals the clear value of puzzles within educational practice,’ said Kath Donovan, director of primary at the learning company Pearson. ‘They can be engaging... but they are not used enough.