Logical inferences according to the Cognitive Development model among Preparatory school students

The research aims to identify the level of logical inferences and its skills among students preparatory stage, & according gender variable (male - female) academic specialization (scientific – literary). sample consisted (400) male female who were selected by random stratified proportional method from three Karkh education directorates. researcher built a test that includes: (6) sub-skills: inference (Proportional, probabilistic, Synthetic, Hypothetical, Syllogistic, Variables Controlling). electrochemical properties verified. following statistical methods used: (Chi-square, Correlation Coefficient: Pearson, Biserial, Spearman Brown Correlation), one-sample t-test, two-way analysis variance). results obtained: 1) Preparatory school possess high inference; 2) stage have more structural hypothetical skill than other skills; 3) degree males is higher in females; 4) scientific Branch literary Branch; 5) Males outperform females Synthetic