"El doble de veinte es cuarenta. Que es el doble de veinticinco?" ("Twice 20 is 40. What is 25 times two?") The quiet boy at the back pricks up his ears. He consults the numbers on his special Spanish ruler and, after only a brief hesitation, puts up his hand to answer. You can almost see him thinking: "This is not maths, it's Spanish." He rarely volunteers, but the introduction of Spanish into the equation renews his energy. Another half hour of arithmetic no longer seems a chore.
Spanish likewise inspires confidence in children baffled by the inconsistencies of English, who find motivation in the simplicity of its spelling. They see their own language in a new light, connecting superficially unrelated words such as "adios" and "goodbye" or "lunes" and "Monday"; all the better if this process also encompasses French, Italian, Latin and German.
Other languages get you thinking about different ways of describing the world and different points of view. Each offers its own philosophical gift. Japanese simply distinguishes between past and non-past tenses and virtually dispenses with plural nouns altogether. Spanish, with the subtle expressive differences between its two verbs for "to be", suggests that Hamlet's dilemma is hopelessly reductive: learning about ser and estar changes the way you see things forever. Learning a language is a liberating game. It frees us from fixed patterns of speech and fixed patterns of thought, shakes things up and inspires the imagination in a similar way to nonsense verse.
Research indicates that scores in core mathematical and verbal skills improve measurably with each year of second-language study regardless of differences in ability or other socio-economic indicators. A lesson in the language lab is equivalent to a solid workout at the gym: one builds bigger biceps, the other bigger brains. Neuroscientists have shown that language learning generates more neurons and more neural pathways: the brain becomes a busier and more productive place, and managing the extra information pays dividends in terms of concentration, discrimination and memory. Multilingual children become better problem-solvers.
Ludwig Wittgenstein wrote that "the limits of our language are the limits of our world". Language learning feeds our brains. So if you want your children to get better at maths and English, don't just do more of them: why not try Spanish instead?
Dr Heather Martin is head of modern languages and curriculum coordinator at St Faith's Independent Prep School in Cambridge
For Spanish sums, try inglesita87's numbers crossword.
Or use rhawkes' Spanish maths logic puzzles to get pupils writing their own.
Find all links and resources at www.tes.co.ukresources041
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