Analysis Of Classroom Scientific Discourse From The Perspective Of Conceptual Construction

In recent years,the abstract function of the model has been gradually applied to the transformation of scientific concepts.The model is not only regarded as a physical object or a reduced-size replica,its unknown function of scientific description and prediction cannot be ignored.In the teaching process,the concept formation is divided into stages from the perspective of model construction,which is helpful to clarify the characteristics of different stages of concept construction.Starting from the real classroom situation,it analyzes how different teachers use utterances to help students construct scientific concepts from the perspectives of the type of teacher-student utterance,the form of dialogue,and the meaning of concept construction in chemistry classes.In order to understand the current status of teacher-student discourse application in chemistry classrooms,explore a good scientific classroom discourse model through comparison,and construct a basis that can help front-line teachers to conduct self-analysis and self-diagnosis.The research questions are as follows:(1)The construction of chemistry concepts,the characteristics of the use of different discourses in the classroom,the characteristics of teachers 'use of discourse in the classroom,the type and amount of discourse,especially the frequency and form of scientific discourse in discourse,the characteristics of teacher-student dialogue,the mode of teacher-student dialogue,teacher What types are there in the process of feedback to students?(2)The construction process of concepts in different stages,the use of teachers 'and students' scientific discourse and the level of students'concept understanding,using the construction process of concepts in different stages in the same core concept system What are the characteristics of discourse,and what is the level of student's conceptual understanding reflected by students' response to discourse?(3)In each stage of concept construction,the difference between teacher and student utterance content and form,and the characteristics of the level of student's conceptual understanding What is the difference between them,and how does different teacher utterances affect the performance of students at the conceptual level?Through combing the literature,the five main stages of the concept construction process are "prototype selection","concept construction","conceptualization","concept analysis and evaluation" and "concept scheduling".Encode and analyze the content and form of the teacher's and student's discourse in the stage,and obtain the level of student's concept understanding from the student's discourse,and analyze the student's concept understanding.In this article,the sample examples are selected from the award-winning works in the National Quality Resource Platform.Such works have a complete classroom structure and rich teacher-student interactions.In order to increase the connection between the samples,under the core concept of middle school chemistry "ion reaction in aqueous solution",three important chemical concepts constructed in different academic stages,namely "acid-base neutralization reaction" and "ion reaction" were selected."Salt hydrolysis" for longitudinal research.(1)Contrastive analysis of discourse distribution during concept construction,in the process of concept construction in the lower stage,teachers often pay more attention to the interaction between scientific concepts and daily concepts,and classroom activities focus on the application and interpretation of scientific concepts in daily life.It is mainly manifested in the prototype stage and the scheduling stage occupying a large amount of speech,using more examples of life,but not too much analysis and deepening of the internal consistency of the concept itself.As students form and perfect the conceptual structure of the system,teaching begins to move the discourse unit from both ends to the middle.Occupy a large amount of discourse in the stages of concept validation,concept analysis and evaluation.The content focuses on the analysis and interpretation of the structural elements of scientific concepts,the coherence between concepts and other concepts in the system,and the students' understanding of concepts The constructive meaning of the concept of relative weakening in real life.(2)Analysis of discourse content and form in the process of concept construction.In different construction stages and different construction tasks,the teachers ' initiating discourse content and the teacher 's response discourse content are closely related to the student's response content.Concluding responses are the main ones;it is worth noting that in the stages of "conceptualization" and "concept analysis and evaluation",the reasoning process of concept connotation and extension is often controlled by the teacher.The closer it is,the more it can be reflected in the discourse.Teacher response words have an important influence on the form of teacher-student interaction.The type of partial response directly determines the development of the speech flow,for example,follow-up questions,asking others to answer,simple responses,etc.In the sample,teachers tend to use "guide-interactive" tendencies to promote the construction of concepts through teaclner-student dialogues,while the discourse mode is mainly "IRFRF".In response to student utterances,teachers often ask students in the form of questioning The existing scientific knowledge is further deepened and analyzed,and teachers and students participate in the interactive process at all stages.(3)The level of concept understanding in the content of student response and the teacher initiated discourse and response discourse analysis.In the process of constructing the concept of low-level chemical science,the content of student activities and students'response words mostly appear in the "prototype selection" and "concept scheduling"stage,and the students' concept understanding level is high,reaching E level;with the complexity of the concept relationship As the degree increases,during the "prototype selection" stage,students'response to conceptual understanding decreases slightly;during the" concept construction "stage,the student's vocabulary decreases significantly,and the level of conceptual understanding is also low;as the complexity of the conceptual structure increases;"Effective" and "concept analysis and evaluation" stages gradually increase the level of conceptual understanding;"concept scheduling" stage student response content has a wider scope and reflects the student's concept hierarchy,and is closely related to teachers' teaching wits and activity arrangements.The recommendations made are as follows:(1)Explore the connection between conceptual elements and scientific concepts in the context to provide support for the construction of concepts.(2)Pay attention to the stage of concept construction and design and construct links in a targeted manner.(3)Teacher discourses focus on the high-level discourse of students Promote students to actively participate in concept construction.