Numerous methods are employed to teach mathematics. One of them is posing questions in the math class. This study is intended to investigate the effects of Posing-Good-Questions Method (PGQM) on math achievement of the high school first graders in comparison to traditional math teaching methods. The present study is quasi-experimental with experiment and control groups. Research sample consists of 71 girl high school first graders selected through cluster sampling. Instrumentation used by the study is a teacher-made school achievement test. The results obtained from paired samples test, Mann-Whitney and Wilcaxon test found that there is no significant difference between experiment and control groups with this regard. It suggests that owing to some unknown educational barriers, PGQM yields no math achievement among high school students.