chapter  6
Arithmetic Procedures are Induced from Examples
Pages 48

Supposeoneaskedsomeconcernedadults.forexample,parents,howmulticolumnsubtractionislearnedinschool.Theirexplanationwouldprobablyrun somethinglikethis:Theteachertellsthestudentshowtoperformthealgorithm, thensetsthemtosolvingpracticeexercises.Perhapsthepracticecausessome studentstorealizethattheyhadn'tquiteunderstoodwhattheteachermeant.Or perhapstheteachernoticesthatcertainstudentsarefollowingthewrongprocedure.Ineithercase,theteacherhelpsthestudentsbytellingtheminmore detailaboutthealgorithm,probablybyadaptingtheexplanationtotheparticular exercisesthatthestudentsareworkingon.Tellingdominatesboththeinitial instructionandthesubsequentteacher-studentinteractions,accordingtothisfolk modelofarithmeticacquisition.Winston(1978)dubbedthismodel"learningby beingtold."