Adolescence and secondary mathematics: shifts of perspective Anne Watson December 2008 Adolescence: social identity feeling powerful belonging understanding the world being heard being in charge negotiating authority being supported arguing in ways which make adults listen Adolescence: emotional Self-concept, motivation, engagement etc. In all school subjects there is more difference between students in these aspects than between classes and schools BUT in maths, there is significant difference between classes in orientation, self-handicapping, disengagement, enjoyment of the subject, aspirations, and teacher-student relationships – significantly higher than in any other subject Adolescence: the brain Massive reorganisation of neural networks in parts which organise interactions, making sense of social situations, relating to the world What the reorganisation IS or DOES no one yet knows – but it does seem to be associated with perception, interaction and talk Adolescence: the mind Acceleration of development of social and intellectual capabilities: Focusing on salient factors/editing out irrelevant factors Comparing relationships Dealing with conflicting situations Retracing steps of argument Chunking/objectifying/abstracting Unambiguous classification Comparing across classifications Anticipation/ imagining reality Extending ideas of similarity beyond the visual Focusing on salient factors/editing out irrelevant factors Propensity to generalise from what is available May over-generalise; generalise irrelevant features if they don’t know what is relevant Comparing relationships Comparing differences and ratios Comparing outcomes of operations Reasoning about relationships rather than objects and quantities Dealing with conflicting situations Extending old ideas to new meanings Reorganising earlier understandings Redefining Retracing steps of argument Can review arguments Can reapply arguments Can reverse arguments Chunking/objectifying/abstracting Building new concepts from old Using ‘new’ language with meaning Results of old procedures being new objects Unambiguous classification Be precise about classification Need to resolve ambiguity Return to class inclusion Comparing across classifications Sameness and difference as raw material for new ideas, or for distinguishing between old ideas Anticipation/ imagining reality Extend beyond available range of application Extend beyond visual representations Turn imagined action into other representations Extending ideas of similarity beyond the visual Focus on properties, not appearance Focus on process and mechanisms rather than visual output Focusing on salient factors/editing out irrelevant factors Assuming all graphs go through the origin; assuming all rectangles are parallel to edge of pages Teaching: choose range of examples Comparing relationships Rates of change; distributive law (order of operations); equations as objects Teaching: focus on relationship as object; focus on structure of expressions Dealing with conflicting situations Multiplication and addition do not ‘make things bigger’; ‘more digits’ does not mean ‘bigger number’ Teaching: recognise conflicts (not errors) and give time to discuss new meanings Retracing steps of argument Inverse operations; express reasoning; refine reasoning (proof) Teaching: encourage expressing and retracing arguments; ask students to re-work worked examples; inner language Chunking/objectifying/abstracting Number as a product of prime factors Equation as the ‘name’ of a function Ratio as a new arithmetical object Unambiguous classification Sort out names of shapes inclusion and exclusion; proportions in shapes and proportional relationships; discrete v. continuous Teaching: use technical terms in talk; relate words and classifications; deal with ambiguity Comparing across classifications Compare linear graphs to proportional functions; compare sine to cosine; compare ‘regular’ to ‘symmetrical’ Teaching: use ‘same/different’ as frequent classroom tool Anticipation/ imagining reality What will happen when x = 0? What will happen when n becomes very big? What will happen when the wheel turns through 360°? What sort of function might fit this data? Teaching: encourage conjecture; focus on the power of special examples; change representations Extending ideas of similarity beyond the visual What is the same about all pentagons in all orientations? What is the difference between bar charts and histograms? Teaching: talk about properties and the difference between what you see and what you know Adolescent learning/ mathematics learning from ad hoc and visual reponses to abstract ideas and prediction from imagined fantasy to imagined actuality with constraints and consequences from intuitive notions to ‘scientific’ notions from empirical approaches to reasoned approaches from doing to controlling Key ‘learnable-teachable’ shifts in secondary mathematics Discrete – continuous Additive – multiplicative exponential Procedures as rules – procedures as tools Examples– generalisations Perceptions – conceptions Operations & inversesstructures and relations Reading signs – reading meaning Patterns – properties Assumptions of linearitythinking about variation Getting results – reflection on method and results Inductive/empirical reasoning – deductive reasoning Synthesis of research on how children learn mathematics (Nuffield) Bryant, Nunes, Watson Watch this space …. Watson (2006) Raising Achievement in Secondary Mathematics (Open University Press) Watson & Mason (2006) anne.watson@education.ox.ac.uk www.cmtp.co.uk Mathematics as a Constructive Activity (Erlbaum)