This study aims to investigate students' positions and values applied during decision-making processes on
socioscientific issues (SSI), and to describe the patterns of change that occur in the students' decision-making. Thirteen high
school students participated in the SSI program and the discussion topics of the SSI program were as follows: cloning, animal
experimentation, MERS Corona Virus, global warming. We collected qualitative data which consisted of a pre and post interview
of each student, the SSI group discussion, and worksheets that students responded before and after the SSI group discussion.
As a result, the data showed that students tended to make decisions by applying 7 values; personal values, economic
values, scientific values, rights and obligations, social values, ethical values, and medical values. The SSI instruction caused
changes in the students‘ decision-making patterns which were categorized into 4 different types: (a) students who displayed
consistent values and maintained the same position, (b) students who kept the same position but showed more diverse values
and perspectives, (c) students who showed more diverse values and perspectives, and changed their position, and (d) students
who showed more diverse values and perspectives, and took the opposite position. The students who changed their position
tended to consider the reasons of the contrary position and took into account a variety of perspectives. Therefore, to improve
students' decision-making skills, the SSI discussion program should be developed and utilized more widely.