课堂教学活动是一个富于变化的共时空群体活动,主体、客体、媒体之间的关系处在不断转化之中。教学的进程不可能在设计时加以全部预测。只有从鲜活的学情出发,全面充分地预测学情,进行弹性预计,为生成留足空白、腾出空间,这样才能充分利用生成性资源,调动学生学习的积极性。 Classroom teaching activities are a group of activities that are full of changes in time and space, and the relationship among subject, object and media is constantly changing. Teaching process can not be fully predicted at design time. Only starting from fresh learning conditions, fully and fully predicting the learning situation, making flexible predictions, leaving gaps for development and making room for them can we make full use of generative resources and mobilize students’ enthusiasm for learning.