Vol. 7 Num. 2 (1987) Sherman K. Stein Gresham's law: algorithm drives out thought2 Robert P. Hunting Mathematics and Australian Aboriginal culture5 Gilah C. Leder The mathematics classroom: mature reflections11 Abraham Arcavi , Maxim Bruckheimer , Ruth Ben-Zvi History of mathematics for teachers: the case of irrational numbers18 Jennifer Macpherson Norman24 George Stanic , Laurie Hart Reyes Excellence and equity in mathematics classrooms27 Celia Hoyles Tools for learning -- insights for the mathematics educator from a Logo programming environment32 Uri Fidelman A cerebral basis for an ontology of mathematics and physics38 Jan van den Brink Children as arithmetic book authors44