High School Chemistry Demonstration Formula Based On PCRR Model Research On Teaching Practice

At present,how to cultivate students' scientific literacy has become the focus of the international education circle.Scientific demonstration,as an important part of scientific literacy,is strongly emphasized in the international large-scale scientific literacy test and the curriculum reform around the world.Scientific argumentation teaching is the primary way to develop students' scientific argumentation quality,so it has been continuously explored and practiced by researchers from various countries.The research on the teaching of scientific argumentation in international science education started early and is now mature,but the relevant research in China is still in the initial stage,so it should be attached great importance.This research mainly includes literature review,instructional design and empirical research.In the literature review,the author mainly makes literature statistics on the related research of scientific argumentation teaching at home and abroad,and summarizes it from the perspectives of origin and development,value,strategy and model.Then it elaborates the theoretical basis of this research--Tulmin's argumentation model.Then,the PCRR(Present,Critique,Reflect,Refine)demonstration teaching model is selected and analyzed,that is,including demonstration teaching links of presenting,criticizing,reflecting and refining four cycles.Finally,the empirical research,specific process is: choose the jingning county,gansu province two classes,a middle school as the experimental class and that in comparative classes and experimental classes using PCRR teaching model,use the traditional teaching mode that in comparative classes,quasi-experimental method and questionnaire method is adopted to improve the teaching practice,and random five chemistry teacher in our region and five classes students conducted semi-structured interviews.The main research questions of this study are as follows:(1)to analyze the development of students' scientific argumentation tendency,scientific attitude,scientific argumentation ability,chemistry learning interest and unit subject knowledge in the pre-and post-teaching tests of experimental class and control class;(2)through student interviews,students in the experimental class were informed of their views on thePCRR teaching model,and through random interviews with teachers,the application status of scientific argumentation teaching in first-line classrooms was understood.The results show that after 3 weeks of teaching practice,(1)the scores of the experimental class are significantly higher than the control class in the three aspects of scientific argumentation tendency,scientific attitude and interest in chemistry learning.(2)in terms of the overall score of scientific argumentation ability,the experimental class was significantly higher than the control class,but the development of the five sub-dimensions was unbalanced.There was no significant difference in the two sub-dimensions of proposition and counter-argument,but there was significant difference in the three sub-dimensions of material or evidence,justification and refutation.(3)there is no significant difference in the short-term average score in the unit subject knowledge assessment,but the average score of the experimental class is about 1 point higher than that of the control class;(4)the current situation of scientific argumentation teaching in the frontline is conscious but insufficient in application;Students in the experimental class agree with and adapt to the PCRR teaching model as a whole,and put forward relevant Suggestions.The conclusion is that the PCRR model is helpful to improve students' scientific argumentation tendency,scientific attitude and interest in chemistry.PCRR model to improve the students' ability of scientific reasoning,but the vast majority in the medium level,high level of very few,the students' ability to question and counter is still relatively weak,so need long-term argument teaching intervention to achieve a high quality of the argument,this also reflected from the side the higher order thinking and critical thinking ability of students as a whole is relatively weak;Although there is no obvious difference in students' unit subject knowledge in a short time,the experimental class is better than the control class in terms of average score and classroom performance,which indicates that the PCRR model is conducive to students' independent construction of scientific concepts.In a word,PCRR is a new and effective scientific argumentation teaching model,which is in line with the current core literacy oriented new curriculum concept.It is expected to be strongly advocated by relevant education leaders and provide some necessary support for front-line teachers to be actively explored,tried and practiced in today's science education and teaching.