The main goal of this study is to find out the effect of the instructional design method on the enhancement of problem solving abilities of students. Teaching sessions were applied to ten students who are in 11th grade, to teach them problem solving strategies which are working backwards, finding pattern, adopting a different point of view, solving a simpler analogous problem, extreme cases, make drawing, intelligent guessing and testing, accounting all possibilities, organizing data, logical reasoning. Our study based on one-on-one (teacher-experimenter and student) design experiments where we conduct teaching sessions with a small group of students to study in depth and detail. We designed sessions to teach high school students, problem-solving strategies in a ten-week long period. Before and after the application of instructional design, 12 different problems were given to students. We made interviews with students about their opinions on the effect of this design. At the end of the analysis, we observed that the instructional design improved students on choosing and applying an appropriate strategy. In addition to this, students became aware of the existence of several different problem-solving strategies and they realized that they could use more than one strategy for a problem. [This study was presented as an oral presentation at 16th Conference on Problem Solving in Mathematics Education (ProMath), University of Helsinki, 27-30 May 2014, Helsinki, Finland.]