# Students’ Conceptual Understanding on Division with Decimals in Mathematics Classroom

## Abstract

This research aims to analysis and understand the conceptual knowledge of students about dividing decimals in mathematics classes that uses lesson study classroom through the method of Open Approach. The target group of this research is 15 primary school students in the academic year 1/2020 at Ban Bueng Niam Bueng Krinoon Tha Hin School. This class manages the study by using an open approach method, the research tools used for data collections were: 7 lesson plans in unit 6 about decimal divisions. The data analysis in this research were 1) protocol 2) students' activity sheet 3) field notes records. Data were analyzed according to the conceptual framework of Kilpatrick et al. (2001)

The study found that: The results showed that mathematics classrooms that uses lesson study in the method of Open Approach is a teaching method that focuses on problem solving processes. There are lesson plans that allow students to learn on their own. They could gain enlightened understanding knowledge effectively.

1.Understanding Concepts
Students demonstrate the principle of decimal division by changing the smallest unit to make decimal numbers into integers and Students show the evidence that the definition of decimal division is to make equal division.
2.Understanding Operations
Students show evidence of the mathematical symbols which include addition (+), subtraction (-), multiplication (×), division (÷) symbols that were used in solving problems. During the process, students can figure out which problem situations should be used with each mathematical symbol.
3. Understanding Relationships

Students show the principles of using different patterns that are related to each other to represent a variety of concepts. Students are able to convert decimal numbers to integers through the mathematical relationship of multiplication and division.. They also have discussions with their friends both in the group and in the whole class to present the relationship of decimal division.

## Article Details

Section
บทความวิจัย (Research Article)

## References

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