| With the continuous development of geography teaching,the core research topics of geography teaching research are also constantly changing with new characteristics and trends.One of the mainstream trends in geography teaching research is the "focus on subject ontology",which purports to discover and solve the unique teaching problems of geography teaching and to reveal the unique teaching rules and principles of geography,and big ideas in geography have received much attention because these big ideas reflect the subject ontology.To some extent,the big ideas in geography is the product of implementing the core literacy of the subject,and unit teaching is an effective way to realize the big idea teaching.As a reflection of the heterogeneity of surface,the earth surface difference is the summary of the differences of the geographical landscape and geographical process on the earth surface,and fundamentally,it is also a direct reflection of regional differences.In the high school geography curriculum,a large proportion of the content relates to the topic of the earth surface difference,which is distributed throughout the mandatory,optional mandatory and elective textbooks.The content of the earth surface difference is extremely complicated.From the perspective of time,the earth surface difference has both dynamic and static forms.From the perspective of space,the earth surface difference is manifested at different scales at both macro and micro levels.Therefore,it is an essential content in high school geography curriculum to learn the earth surface difference.However,after analyzing class teaching cases and reviewing the literature,it seems that the current situation of teaching on the content of the earth surface difference in high school geography curriculum is not satisfactory in the sense that there are lacks of(1)structured understandings of the content of the earth surface difference,and(2)sufficient research on the subject value of geography brought by the earth surface difference as well as on the strategy in embodying such subject value,and(3)focus on the connection between the earth surface difference vis-à-vis the view of human-land coordination,comprehensive thinking,regional cognition,geographic practice,and(4)especially the satisfactory outcomes in cultivating students’ geographic thinking and key geographic abilities through the content of the earth surface difference.This research takes the big idea in geography that "the thermal difference is the basis of the earth surface difference" as a clue,the "unit teaching" as the realization path,and "the earth surface difference" as the main content carrier,focusing on the following four research questions.Firstly,why "the thermal difference is the basis of the earth surface difference" can be used as a big idea in geography? What sub-ideas does it include,and what are the relationships between the sub-ideas? Secondly,what is the explanatory power of "the thermal difference is the basis of the earth surface difference" as a big idea in geography? Thirdly,how to construct the teaching unit for the content of the earth surface difference based upon the big idea in geography that "the thermal difference is the basis of the earth surface difference" ? Fourthly,how to design the unit teaching around the big idea in geography that "the thermal difference is the basis of the earth surface difference" ?This thesis firstly clarifies the research background of this thesis from several aspects,including the important trends of geography teaching research,the characteristics of the teaching of big ideas and the strategies of unit teaching.It clarifies the theoretical significance and practical value of this research on the teaching of big ideas in geography and the earth surface difference,and then puts forward four research goals and problems to be solved and introduces the basic process and the methodology of the research.The theoretical research part of this thesis is mainly to provide answers to the questions of "what are the big ideas?" and "what can the big idea be used for?".The contents of the research consist of two sections.The first section explains the origin of the big idea that "the thermal difference is the basis of the earth surface difference".It uses,in order to confirm the big idea,three logical paths(namely,expert thinking logic,subject knowledge logic,and organizing curriculum content logic)as the "open line",and three main bodies(namely,students,teachers,and experts)as the "dark line",and deeply discusses the confirmation process of the big idea that "the thermal difference is the basis of the earth surface difference".Based on an in-depth theoretical analysis,this article discusses the outcome of refining the big idea and the logical connections between sub-big ideas.This research process provides a comprehensive answer to the question of Research Issue I,where the big idea and its sub-big ideas of that "the thermal difference is the basis of the earth surface difference" are the foundation of the research.In order to ensure the validity and scientificity of the research,this thesis uses the methodology of expert consultation questionnaires to consult experts in this field,in order to determine and refine the big idea that "the thermal difference is the basis of the earth surface difference".Based on the sorting-out and the analysis of the questionnaire,this thesis further revised and improved the determination and refinement process of the big idea,and finally determines the big idea and the four sub-big ideas of that "the thermal difference is the basis of the earth surface difference".The second section of the research discusses the explanatory power of the big idea in geography that "the thermal difference is the basis of the earth surface difference".It initially emphasizes that a deep understanding of "thermal difference" ought to be originated from its generation mechanism and manifestations,and then discusses that how to use "thermal difference" as a logical starting point to provide both an analysis on the causes of and an evolution prediction on the natural geographic processes as well as the natural geographic landscapes and emphases that the analysis of thermal difference and effect outcomes requires attention to its scale and size.This research process provides a comprehensive answer to "Research Issue II".The practical part of this thesis mainly answers the question of "how to use the big ideas?".It consists of two sections.The first section uses the big ideas as the clue to illustrate a general logical path to structure a teaching unit,and in particular,it uses the big idea that "the thermal difference is the basis of the earth surface difference" to structure a teaching unit on the content of the earth surface difference.This research process provides a comprehensive answer to "Research Issue III".The second section determines,by using the structured teaching unit,the general strategies and the logical path to design teaching unit based upon the big ideas,and demonstrates,by using teaching cases,how to conduct teaching unit designs based upon the big idea in geography that "the thermal difference is the basis of the earth surface difference".This research process provides a comprehensive answer to "Research Issue IV".The part of conclusions and prospects of this thesis summarizes the major outcomes regarding the big idea that "the thermal difference is the basis of the earth surface difference" in aspects including the determination,refinement,analysis on the explanatory power of the big ideas in geography,as well as the research on teaching practices based upon big ideas in geography.Meanwhile,it also provides outlooks towards further research directions and reflects on the deficiencies in the research. |
