Is it actually certain that our students are changing during our social studies classes? This paper aims to reveal structural development and evaluation in social studies education which is related to national curriculum requirements and focused on particular students in order to test the effectiveness of the lesson. In order to increase students' concern for the theme, the teacher choose a topic related to the construction of a footbridge on Route 419 on the students' daily route to school as the lesson study unit. The lesson unit took place in a 9th grade class of a Japanese Secondary School, called Asahi Chu-gakko in Kariya, Aichi, for about 40 days from September 21 to October 29, 2010. "Yumiko" is a so-called "case student" among the 37 students that is indicate effectiveness of the lesson through observing in detail his/her performance during the lesson. The authors describe whole learning tracks of the case student Yumiko through pre- and post-Lesson Commentary and Lesson transcripts as evidence of her learning.