Hannah Cooper, 11, of St Crispin’s school, Wokingham, won the under-12s age group of the first Times National Su Doku Championships on Sunday.
Matthew Funnell, 14, of Rickmansworth school, Hertfordshire, won the 12 to 16 age group.
The adult competition was won by Nina Pell, 18, a maths student at Sheffield university, who is from Monmouth, South Wales.