00405nam a2200121Ia 450000500170000000800410001708200150005810000560007324500960012926000340022530000090025965000150026820240821151731.0240821s9999||||xx |||||||||||||| ||und||  a375.51 NAT  aNational Council of Teachers of Mathematics, U.S.A. 0aSignificant changes and trends in the teaching of mathematics throught the world since 1910  aNew YorkbColumbia Univc1929  a186p  aCURRICULUM