การนำเสนอกิจกรรมการเรียนรู้เรื่องการแปลงทางเรขาคณิต สำหรับนักเรียนชั้นมัธยมศึกษาตอนต้น / ยุทธพงศ์ ทิพย์ชาติ = Proposed instructional activities on geometric transformations for lower secondary school students / Yuthapong Tipchat
To propose the instructional activities on geometric transformations for the lower secondary school students. The researcher developed twelve instructional activities on geometric transformations for lower secondary school students by using Thomas Cooney's concepts. These instructional activities were examined by fifteen experts, three mathematicians, three educators in higher education field, and nine secondary mathematics teachers. This research proposed twelve instructional activities on geometric transformations for lower secondary school students which were assessed by fifteen experts, and they were agreed that all twelve instructional activities were concordant to the content, activity, and material aspects, and the IOC were higher than 0.50 in all aspects.