Understanding Primary Children's Thinking and Misconceptions

In Hong Kong, most of the primary school teachers are proud of their students indoing the four operations of decimal numbers. Inspecting a mathematics textbook might givethe impression that, in order to be competent with decimal numbers, all that students need todo is remembering few rules for placing the decimal point, and otherwise perform operationswith decimal numbers as if they were whole numbers. It seems to teachers and parents thatprimary students are able to line up decimal points and count decimal places. However, whenasking a student to compare 4.8 and 4.75, he/she will choose 4.75 as the larger numberbecause 75 is bigger that 8! In fact, the basic concepts of decimal number such as the placevalue and its relation with fraction are discussed at the early stage of learning decimals.However, the discussion is always too simplified and students do not understand thoroughlythe underlying concept of decimal numbers but are pushed to learn the four operations ofdecimal numbers. Thus, students' computational skills on four operations of decimal numbersare merely rote learning and devoid of any meaning. With this reason, the research aimed atdeveloping a tool and using it to uncover students' thinking and misconception on decimals.The significance of this research is to inform our pre-service student teachers and in-serviceteachers the general misconceptions of teaching and learning decimals, so that the focus andframework of teaching decimals could be restructured regarding students' learningdifficulties which were revealed in this research.