Abstract: It is a serious problem in online classes that current formative evaluation of online

teaching is defi- cient. For instance，the situation of students’pre-class preparation and

in-class learning cannot be reflected im- mediately. This has hindered teachers from

targeted teaching and students from autonomous learning. A practical method of teaching

evaluation is proposed in this paper. By designing objective and scientific pre-class and

post- class tests and using the " Rain Classroom" online platform to perform these tests

conveniently，teachers can effi- ciently measure the pre-class and in-class study performance of

any individual student. Thereby，it helps teachers carry out the targeted teaching before，in and

after class. It also helps students find their misunderstanding in their preparation and class

learning，improves their targeted learning and revision，and even stimulate their motivation of

autonomous learning.

Key words: formative evaluation, targeted teaching, autonomous learning