A Case Study On The Secondary School Pupils' Process Of The Representation In Mentality About Solving Irregular Word Problem Relating To Buoyancy

Because the gross of knowledge is blasting in information society , the burden of the second school pupils arose anxiety of people. It is very urgency problem for people to solve that what should be taught over the important and useful period in the second school. Cultivating the core competence is the common sense of the education expert , Problem solving is one of the core competence . Physics is one of more important subject in cultivating it. Through learning physics , student is required to solve problem in real world ,especially to solve new problem when they throw themselves into the cold praxis .However , Many student can solve the regular problem in textbook. Once they meet the actual problem ,they become a idiot of nail-biting . Then what is the process of the representation in mentality of those who are good at solving regular problem of textbook ? what is the distributing of those student ? Solving these problem will build foundation for the reform of education , So it is necessary to advocate the inquiry instruction . Buoyancy is a conception rooted in pupil's real world, the pre-conception about buoyancy is researched clearly in the research institute of science education in Guangxi normal university. Then the information of experience based on pre-conception study , information of number and type of the regular problem was organized in a testing problem . So through solving the testing problem ,the process of representation in mentality is easily distinguished by analyzing student's selecting different information in it . if there is some doubtful point , it can be distinguished by interview with instrument created by the graduate student in the research institute of science education. In the end ,the details of process of thinking was recorded for teaching student in accordance of their aptitude and the statistic of the distributing was calculated for further analyzing, Through analyzing literature and datum , the five main process of representation was summed up .such as : 1: the straitlaced process of symbol representation , 2: the simple process of experience representation, 3: the process of film representation, 4: the process of simulation representation, 5:the process of science and math representation . the characteristic of process of the representation in mentality was generalized , then the distributing on different experience can be ascertained to be analyzed . These was discovered through inquiry .①the process of thinking in a majority of student's mentality is the straitlaced process of symbol representation, the physical formula and the experience of student are almost in different world, this is the process of representation ,the information of number and type of problem is distilled , and the information of experience is neglected, the problem is solved according the modality of example .it is the best way to solve regular problem on the textbook and the exam for its speediness and nicety .but it is the unwieldiness in solving irregular problem of reality. ②The simple process of experience representation was concealed for intense training on regular problem. ③The remained process of representation are employed by few students, hence ,it means few students solve problem through intuition and experimentation. ④Especially ,that the more training in school ,the more process of symbol presentation are employed can be shown in mostly testing problem. ⑤Through inquiry of the pre-conception of buoyancy by predecessor ,the ten strategies are found. The conclusion based on the student's strategies for analyzing the object's circumstance of floating & sinking showed that the strategies that the student utilized mainly are: the strategy of materials, light or heavy, hollow or solid, its density of pressure, of sustain and of moving and so on. The strategies students utilized most are as follows: the material strategy, light or heavy, hollow or solid, pressure and sustain strategy. The testing problem is compiled according one problem mainly embody one strategy which is created as background of experience. The distributing of the straitlaced process of symbol representation is different on different background of experience .A majority of students employed the straitlaced process of symbol representation on the background of experience strategy of face sustain , depth , water sustain , placed mode. It means that many students can't fuse experience and the law of physics into a crystal of wit.。On all account ,the exercise in textbook should not be designed as mathematical problem , but it should be designed to combine students'experience so as to improve the competence of student in solving problem。The evaluation of education should employ irregular problem because regular problem .can be solved by many students only through searching in the store of memory. The inquiry instruction should be advocated because it build the law of physics from inquiring the world of experience.