ABSTRACT
All teachers need to make judgements about pupil attainment, in order to evaluate the effectiveness of their teaching and to inform their planning. In mathematics, it is particularly important to assess what pupils already know because, to an extent, mathematical understanding is hierarchical. It is always possible that some pupils will have already acquired deep-rooted misconceptions about, or difficulties with, certain mathematical ideas. Such misconceptions can have serious implications for the pupils’ ability to comprehend new topics. So teachers assess:
• to inform their planning; • to help diagnose sources of pupils’ difficulties.
