| The study’ purpose was to develop and validate a scale for assessing interest in physics among junior high school students.Hidi and Renninger’s Four-Phase Interest Development Model along with current research literature informed and guided the operational definition of physics learning interest.An exploratory factor analysis resulted in a 16-item scale containing four dimensions: emotion,value,knowledge and engagement.Confirmatory factor analysis suggested the four-factor model fits well in different samples.The Cronbach’s alpha was 0.945,and scale scores showed good internal consistency.The scale was used to investigate 200 junior high school students.It was founded that:(1)Interest in physics was well developed.(2)There was significant difference in genders and regions,and no significant difference in grades for physics learning interest.Strategy(including self-disclosure to infect positive emotions,telling the history of physics to enhance background knowledge and self-selection to promote learning engagement)was proposed to improve students’ interest in physics.Further,two rounds of action research were conducted for the students of the eighth grade.The results showed that the proposed strategy significantly improved students’ interest in physics for junior high school. |