The British Dyslexia Association now has an agreed definition for Development dyscalculia:
“Development dyscalculia is a specific and persistent difficulty in understanding arithmetic and basic number sense. It may also affect retrieval of number facts and key procedures, fluent calculation and interpreting numerical information. It is diverse in character and occurs across all ages and abilities. Dyscalculia is an unexpected difficulty in maths that cannot be explained by external factors.
Maths difficulties are often thought of as a continuum, not a distinct category, with dyscalculia at the extreme end of this continuum. It should be expected that developmental dyscalculia will be distinguishable from general maths difficulties due to the severity of difficulties with symbolic and non-symbolic magnitude, number sense and subitising.
Developmental dyscalculia can often co-occur with other specific learning difficulties, such as dyslexia, dyspraxia and attention deficit hyperactive disorder.”
Children with dyscalculia can not be taught maths by teaching at a slower pace than children who do not have the condition. Specialist interventions are required and these may depend on the needs of each child: