十几减876参考ppt课件.ppt

1,十几减,8,、,7,、,6,2,看屏幕口算。,11,9,11,8,13,9,16,9,12,8,14,8,15,9,15,8,12,9,17,8,14,9,13,8,17,9,16,8,18,9,2,7,4,3,4,7,6,6,3,5,5,9,8,9,8,3,问题：,1.,根据图意，你能提出数学问题吗？先独立思考，,再同桌交流。,2.,谁来说说你提出了什么问题？,（一）收集信息，提出问题,13,条金鱼，红的有,6,条，黑的有几条？,13,条金鱼，黑的有,7,条，红的有几条？,3.,你能根据提出的问题列式解答吗？,13,6,13,7,一共有,13,条金鱼。,4,（二）自主探究，暴露资源,反馈：,1.13,6,6,13,13,6,13,6,7,3,10,4,7,7,7,5,反馈：,2.13,7,7,13,13,7,13,7,6,3,10,3,6,6,6,6,1.,摆摆，说说，算算。,6,8,6,8,6,6,7,7,7,2.,算一算。,17,15,16,9,8,6,9,9,7,8,3.,问题：（,1,）从图中你都知道了什么？,（,3,）你想怎样解答？,（,2,）要求的问题是什么？,15 7,15 6,8,9,9,1,1,9,=,2,1,2,9=,3,1,3,9=,4,1,4,9=,5,1,5,9=,6,1,6,9=,7,1,7,9=,8,1,8,9=,9,十几减,9,，,等于几加,1,10,11,8=,12,8=,13,8=,14,8=,15,8=,16,8=,17,8=,你发现了什么？,3,4,5,6,7,8,9,11,1,1,8,=,3,1,2,8=,4,1,3,8=,5,1,4,8=,6,1,5,8=,7,1,6,8=,8,十几减,8,，,等于几加,2,12,11,7=,12,7=,13,7=,14,7=,15,7=,16,7=,你发现了什么？,4,5,6,7,8,9,13,1,1,7,=,4,1,2,7=,5,1,3,7=,6,1,4,7=,7,1,5,7=,8,1,6,7=,9,十几减,7,，,等于几加,3,14,11,6=,12,6=,13,6=,14,6=,15,6=,你发现了什么？,5,6,7,8,9,15,1,1,6,=,5,1,2,6=,6,1,3,6=,7,1,4,6=,8,1,5,6=,9,十几减,6,，,等于几加,4,16,破十法儿歌,退位减，我会算,十几减,9,，等于几加,1,，,十几减,8,，等于几加,2,，,十几减,7,，等于几加,3,，,十几减,6,，等于几加,4,，,17,9,5,8,2,6,15,6 13,8 14,7,17,9 11,9 12,6,7,送信,18,11,8=,13,7=,13,6=,18,9=,15,8=,17,9=,11,7=,14,6=,3,6,7,9,7,8,4,8,15,9=,12,7=,13,9=,15,7=,11,6=,16,9=,17,8=,14,8=,6,5,4,8,5,7,9,6,19,四、布置作业,作业：第,14,页“做一做”第,3,题。,第,15,页练习三，第,4,题。,