Abstract:
The purpose of this research were: 1) to create instructional packages on the topic of integers for for the 7th grade students to meet a defined efficiency of 70/70, and 2) to examine the mathematical learning achievement base on the instructional packages on the topic of integers for the 7th grade students. The sample in this research was 30 7th grade students, Academic Year 2020, ChamnanSamakkhiwittaya School who have integers' learning achievement lower than the criterion of 50% and voluntarily join the research project. The research instrument consisted of the instructional packages on the topic of integers, mathematical learning lesson plans, and a mathematical learning achievement test. The data was was analyzed using mean, percentage, and standard deviation. The findings revealed that: 1) the efficiency of the developed instructional packages on the topic of integers reached 76.31/71.17, which was higher than the defined criteria of 70/70, and 2) the effectiveness index (E.I.) of students mathematical learning achievement achieved 0.63, which was higher than the set criteria of 0.6. This could be concluded that the students gained knowledge and achieved greater learning development.