. . "Mathematics Study and teaching (Elementary)" . . "Australia." . . "Addition." . . "National Institute of Education (U.S.)" . . "University of Tasmania." . . "Mathématiques Étude et enseignement (Primaire)" . . "Wisconsin Center for Education Research." . . "Observation (Educational method)" . . "Subtraction." . . "Mathematics Study and teaching (Elementary) Australia." . . . . . . . . . . . . . . . . . "Classroom learning : results from observations" . . "Classroom learning : results from observations"@en . . . . "Classroom learning results from observations--Sandy Bay study"@en . . . . . . . . "Classroom learning : results from observations--Sandy Bay study"@en . . . . . . . .