In the form of "Do, Check , Action and Plan"(DCAP)-style, my teaching practice and improvementse will be presented. Towards firm understanding of physics, we have to know students learning status. First we have to know how to sieze students' learning mind and motivate them to learn physics by on-cite demonstration (experiment) and looking back daily seen physics phenomena, sucessive questions and answer dialogues with students. Partly series of complex expreiment pre-recorded as movie are also shown after the on-cite experiments. (Do part). With such dialogue teacher can know the students' learning status and decide the effective starting point to teach physics, that is where to start including topics of past grade. And the evaluation of students are based on mid-term and final examination, which are analyzed in terms of cause of wrong answers and how they would understand the right notion in logical way without blindedly remembering series of fomula of physics(Check part). After taking quetionare of students' opinion, I made feed back to students' opinion and made some concrete suggestion intended for modification to right studying attitude(Action part). At last I will present next years' instructional design of physics(plan part) all with my 14 years' teaching experience of physics incooperated with the results of former Do-Check-Action of experience of teaching physics. Especially introduction of pre-required notion before starting the theme of physics in the sence that students can share required information they should understand and where they are and where they are going will be focused. Instruction in terms of verval understanding of physics formula is included.