Teachers recognize that students may successfully perform diverse actions and not understand what they have done. Several classroom techniques are employed to increase students' comprehension, such as giving more time to practice and accepting students'"growth" errors. In order to understand, children must be given the opportunity to construct their own understanding, even though a mismatch may occur between their representations of their thinking and conventional symbols. A true representation, though, reflects what a child is thinking at a certain time, not what adults think the child should be thinking. Gaining understanding involves reflexive abstraction: a projection of experiences to a higher level and a reorganization of experience at that higher level. For example, children who successfully build numbers with Dienes Blocks may then project that experience mentally and reorganize it with mathematical symbols to reflect their work. Children's increasingly systematic competence at a task is a clue that they are ready to become conscious of what they are doing. Over time a match between children's symbols and conventional symbols will occur. The developmental teacher is aware of the difference between success and understanding and encourages children to go beyond the right answers to attain understanding of the rules that lead to the right answers. (RH)