Ms Anne Thrope is spot on when she refers to the damage caused by "ability" grouping ("The wrong sort", 20 July). Having worked with "low ability" and "high ability" groups in key stage 2 maths lessons, I can see nothing to recommend this system that is not outweighed by its negative aspects. Children in the low-ability group think they are the "stupid table". Children in the high-ability group are often too afraid of losing status to admit that they don't understand a concept.
Helen Salthouse, Banstead, Surrey.