根据人教版小学数学的课程设计要求,学生在了解和学习了正方形和长方形面积的计算公式之后,学习推导平行四边形、三角形和梯形的面积.学习这些基础图形面积的过程中,要注重与以前学习的图形相联系,需转换思维,将要求解和学习的图形进行分割、移补等,转换为已经掌握的图形,从而求解其面积. According to the PEP mathematics curriculum design requirements, students learn to learn the square and rectangular area of ​​the formula, learn to derive the area of ​​parallelogram, triangle and trapezoid.Study these basic graphics area, pay attention to the previous Learn the graphics associated with the need to change thinking, will be required to solve and learn the graphics segmentation, compensation, etc., has been mastered into the graphics to solve its area.