人教版教材五年级上册“多边形的面积”单元,是在学生认识三角形、平行四边形和梯形,理解了面积的概念,会计算长方形、正方形面积的基础上,进一步学习平行四边形、三角形和梯形的面积,形成有关多边形面积的系统知识。在以往的教学中,这些教学内容的编排往往侧重于理解和掌握图形 PEP textbook grade five “polygon area ” unit is based on the students to understand the concept of triangle, parallelogram and trapezoid, understand the concept of area will be calculated on the basis of rectangular, square, to further study the parallelogram, triangle and The area of ​​the trapezoid forms a systematic knowledge of the area of ​​the polygon. In previous teaching, the arrangement of these teaching content often focused on understanding and mastering graphics