Mathematics and Science Education 19 August - 30 August 2013 Realistic Mathematics Education – A teaching approach that makes sense Marja van den Heuvel-Panhuizen Freudenthal Institute Faculty of Science Faculty of Social and Behavioural Sciences Faculty of Social and Behavioural Sciences Faculty of Science Secundary Education Early Childhood Special Education Primary Education Vocational Education Freudenthal Institute Realistic Mathematics Education • “real world mathematics” • to imagine = ZICH REALISEREN • context-based real world or fantasy world formal world of mathematics Realistic Mathematics Education Freudenthal Institute 1971 - .... ~1968 2013 • still under construction • over the years different accentuations Mechanistic mathematics education Realistic Mathematics Education New Maths ~1968 Grade 3 1969 (9e edition) Grade 3 2013 % market share RME textbooks % market share Mechanistic textbooks 1960s 1980s 1987 1992 1997 2004 Mechanistic Mathematics Education Realistic Mathematics Education - bare number calculations - activity principle - reality principle - level principle - intertwinement principle - interactivity principle - guidance principle - little attention applications (especially not at start) - teaching is transmission * atomized * step-by-step Realistic Mathematics Education transmission approach to learning applications target constructivist approach to learning applications applications source target TIMSS 2003 Study - Grade 8 International average: 38% got a full credit Dutch students: 74% got a full credit Freudenthal Rather than beginning with abstractions or definitions to be applied later, one must start with rich contexts that ask for mathematical organization; or, in other words, one must start with contexts that can be mathematized. “What humans have to learn is not mathematics as a closed system, but rather as an activity, the process of mathematizing reality and if possible even that of mathematizing mathematics.” (1968) Treffers 1987 (Three Dimensions) mathematizing “real” world 1 2 mathematics Realistic Mathematics Education – various levels of understanding – progressive schematization – models as bridges - activity principle - reality principle - level principle - intertwinement principle - interactivity principle - guidance principle Grade 1 Grade 1 formal calculation 1 5 1 1 5 1 1 1 1 1 1 1 1 1 1 1 1 1 cross-section six and six is ... calculation by structuring calculation by counting calculation by structuring longitudinal-section formal calculation Treffers 1987 (Three Dimensions) Progressive schematization Progressive ‘complexization’ Progressive schematization 12 6394 1200 5194 1200 3994 1200 2794 1200 1594 1200 394 120 274 120 154 120 34 24 10 12 100 100 100 100 100 10 10 10 2 532 r. 10 6394 2400 3994 2400 1594 1200 394 360 34 24 10 12 200 200 100 30 2 532 r. 10 6394 6000 394 360 34 24 10 12 500 30 2 532 r. 10 6394 532 60 39 36 34 24 r. 10 whole-number-based written calculation 53 5459 5300 159 159 0 100 3 103 digit-based written calculation 53 5459 103 53 15 0 159 159 0 Streefland 1985 (Wiskunde als activiteit en de realiteit als bron) 1996 (Learning from history for teaching in the future) Models as bridges: Model of → Model for bus stop model of on 31 model for off on 39 difference minimal or more off On which table do you get more? model of or Which fraction is larger ? 15 or 6 12 8 model for 3 6 4 8 Mathematics in Context mathematics textbook series for grades 5-8 Romberg (Ed.) (1997-1998 ...) Grade 5 (- 6) Learning trajectory for percentage qualitative/informal way of working with percentage percentage as descriptors of so-many-out-of-somany situations quantitative/formal way of working with percentage percentage as operators Informal knowledge How busy will the school theater be? Color the part that will be occupied and write down the percentage of occupied seats Emergence of the bar model Emergence of the bar model Occupation meter 60 out of 80 50 out of 85 36 out of 40 Bar as an estimation model Poll about favorite baseball souvenir Giants fans (310): 123 vote for cap Dodgers fans (198): 99 vote for cap Which fans like the cap the best? Introduction of 1% benchmark Calculating via 1% Year Total Number Percent of number of of marathon of drop outs drop outs runners Describe your strategy Directly dividing by the whole number 1% is 600÷100 = 6 121 ÷ 6 ≈ 20 121 ÷ 6 = 20.166666 ≈ 20 121÷600 = 0.20166666 ≈ 0.20 Jimenez 20% Jacobs 25% Peresini Fulhouse 30% 15% 10% Situations of change - prices Additive way: ‒ 25% 75% $3.20 ÷4 = $0.80 $3.20 ‒ $0.80 = $2.40 Multiplicative way: x 0.75 $3.20 x 0.75 = $2.40 Check the sale price by making just one calculation on you calculator 80% x 0.8 80% x 0.8 64% x (0.8 x 0.8) is x 0.64 Situations of change – interest-bearing account $447.71 after 1 year: $250 x 1.06 after 2 years: $250 x 1.06 x 1.06 after 3 years: $250 x 1.06 x 1.06 x 1.06 after 4 years: $250 x 1.06 x 1.06 x 1.06 x 1.06 after 5 years: $250 x 1.06 x 1.06 x 1.06 x 1.06 x 1.06 = $354.63 sale price sale price 75% 100% 96 ? x 0.75 ÷ 0.75 original price original price Shifts in function of the bar model representational model estimation model Year of marathon calculation model thought model Total number of runners Number of drop outs Percent of drop outs Describe your strategy shifts in context domain function contextconnected/ informal level of understanding model of of for model for of for and so on of for general/ formal level of understanding model of Realistic Mathematics Education model for your teaching Thank you m.vandenheuvel@fi.uu.nl http://www.staff.science.uu.nl/~heuve108/download/summer-school-readings