Secondary High School Chemistry Classroom Teaching Problem Chain Design

Questioning is one of the most effective bilateral activities between teacher and students in the class, which is not only an important channel for both output and feedback to teachers, but also could cultivate students'learning interests and creative ability. However, there are still some phenomena of invalid questioning, such as random questioning, lacking of inspiration in the chemistry class. The main reason is the lack of viable bracket when teachers are designing questions.In the paper, firstly, the video records of typical chemistry teachers in junior high school are selected as the content for analysis. The questioning levels of the two teachers are classified and compared according to questions classification on the cognitive level of Broome and two dimensional questions classification of Davies. Based on the statistics, we analyze the typical lessons of the teachers from the perspective of the question chain and know the major differences of questioning between novice teachers and proficient teachers. In the meanwhile, we find the main problems existed in the chemistry class in secondary school. Then, for the current problems in classroom questioning, a scaffold of designing questions is explored on the basis of the logic of subject knowledge and student cognition. Through observing perfect lessons combined with theoretical research, several typical design models of questioning chain are summarized.The research shows that high-density questioning has changed the traditional teaching ways with cramming teaching and passive accepting all kinds of declarative knowledge for students in chemistry class of secondary school. As to question level, whether for novice or proficient teachers, low-level questions are the majority, the proportion of high-level questions are lower, but proficient teachers pay more attention to those questions that could improve the comprehensive talent and ability of the students than the novice teachers such as analysis, synthesis and evaluation. the closed questions of both novice and proficient teachers are the majority, the proportion of open-ended questions are lower. However, proficient teachers are apt to solve open-ended questions in "focusing strategy of questioning".This paper focuses on mining the characteristics of chemical subject and students' cognition in theory and bringing in the "five W" to chemistry teaching. In addition, a question designing strategy model is put forward integrated the logic of subject knowledge and student cognition.