Dyscalculia is a difficulty understanding mathematical concepts and symbols. It is characterised by an inability to understand simple number concepts and to master basic numeracy skills. There are likely to be difficulties dealing with numbers at very elementary levels; this includes learning number facts and procedures, telling the time, time keeping, understanding quantity, prices and money. Even if the child produces a correct answer or uses a correct method, he/she may do so mechanically and without confidence.

Difficulties with numeracy and mathematics are also common with dyslexia.
Does dyscalculia also affect people with dyslexia?
  • Research suggests that 40-50% of dyslexics show no signs of dyscalculia. They perform at least as well in mathematics as other children, with about 10% achieving at a higher level.
  • The remaining 50-60% do have difficulties with mathematics. Not surprisingly, difficulty in decoding written words can transfer across into a difficulty in decoding mathematical notation and symbols.
  • For some dyslexic pupils, however, difficulty with mathematics may in fact stem from problems with the language surrounding mathematical questions rather than with number concepts – e.g. their dyslexia may cause them to misunderstand the wording of a question.
  • In summary, dyscalculia and dyslexia occur both independently of each other and together. The strategies for dealing with dyscalculia will be fundamentally the same whether or not the learner is also dyslexic.
Typical symptoms of dyscalculia.
  • Counting: Dyscalculic children can usually learn the sequence of counting words, but may have difficulty navigating back and forth, especially in twos and threes.
  • Calculations: Dyscalculic children find learning and recalling number facts difficult. They often lack confidence even when they produce the correct answer. They also fail to use rules and procedures to build on known facts. For example, they may know that 5+3=8, but not realise that, therefore, 3+5=8 or that 5+4=9.
  • Numbers with zeros: Dyscalculic children may find it difficult to grasp that the words ten, hundred and thousand have the same relationship to each other as the numerals 10, 100 and 1000.
  • Measures: Dyscalculic children often have difficulty with operations such as handling money or telling the time. They may also have problems with concepts such as speed (miles per hour) or temperature.
  • Direction/orientation: Dyscalculic children may have difficulty understanding spatial orientation (including left and right) causing difficulties in following directions or with map reading.

Dyscalculic children may be particularly vulnerable where teachers follow an interactive, whole-class method of teaching as recommended by the National Numeracy Strategy. Asking dyscalculic children to answer apparently simple maths questions in public will inevitably lead to embarrassment and frustration.