In this study, by using materials that are said to be effective for skill acquisition of the straddle vault skill of long-box, the collection of cases of instruction-words toward students' various failures which occur when students learn straddle vault skill are made by three primary school teachers who took the classes and by the researcher. Referring to the teaching material and the collection of cases of instruction-words, those three teachers planed an original unit (6 hours) of long-box activity and practiced. Therefore the purpose of this paper is to analyze the lessons for students who fail to jump long-box from the perspectives of an order of lesson plan, arrangements and usage of lower teaching materials and effects of teachers' teaching behavior toward students.
As a result, to design appropriate lesson plans for students, to give appropriate teaching materials according to each student's ability and to give appropriate tasks and verbal feedbacks (teachers' behavior) are necessary to guarantee students the basic straddle vault skill of long-box.