Difficulties in acquiring knowledge and skills to the normal level expected of those of the same age, especially because of mental disability or cognitive disorder.
Some children are more likely to learn properly than others. There are plenty of causes which can explain why certain pupils face learning difficulties: They may be in poor health, they may be less able to learn (innate ability), they may have a mother language different from the working language of the school, they may belong to a family which has less motivation for supporting school values than others, or they may be exposed to a shorter study time, both inside and outside the school (Postlethwaite, 2004: 12).