This study aimed to Investigate the Effectiveness of a proposed Training in developing mathematics teachers' skill in posing classroom questions into different cognitive levels. The study sample consisted of (13) mathematics teachers from Bahla Basic Education School (5-10).First, the researcher used a classroom observation in order to record all the classroom questions which used by mathematics teachers inside the classroom. Then, the researcher used a Training Program to train mathematics teachers on how to ask different levels of cognitive questions according Deltz terminology. It is reviewed and validated by some mathematical education specialists. According to the reliability, it is equal 0.83. To answer the questions of this study, the researcher used SPSS statistical program. In answering the first question he used frequencies and percentages and for the second used wilcoxon test. Finally, the study findings shows that: The classroom questions are more Diverse and tended to high levels for instance grades (seventh , eighth and ninth). • There was a statistical significant differences between pre and post measurements at the level of (a = 0.05) in favor of the post measurement.