Program using Cort to teach thinking and its impact on Cognitive flexibility And some advanced tennis skills

The research aims to identify the effect of a program using Cort to teach thinking on the cognitive flexibility and some advanced skills (The drop shot-The Smash-the Volley- the Lob) in tennis for students of tennis specialization in the Faculty of Physical Education for Girls Zagazig University.
Research hypotheses:
- There are statistically significant differences between the averages of the pre and post measurements of the control group in the cognitive flexibility and learning some advanced skills (The drop shot-The Smash-the Volley- The Lob) in tennis in favor of post measurment.
- There are statistically significant differences between the averages of the pre and post measurements of the experimental group in the cognitive flexibility and learning some advanced skills in tennis under research in favor of post measurment.
- There are statistically significant differences between the two post measurements of the control and experimental group in cognitive flexibility and learning some advanced tennis skills under consideration in favor of the experimental group.
Research procedures:
Research Methodology:
The researcher used the experimental method of pre-post measurements for two groups, one experimental and the other is a control group, as to suit the purpose of the research.
Research Society and Sample:
Representing the third year students of the Faculty of Physical Education for Girls - 
Zagazig University for the academic year 2017/2018 tennis specialization, consisting of (80) female students.
The research sample:
Two groups, one experimental and one control each, (20) students were selected randomly.
The researcher calculated the equilibrium distribution of the members of the research sample, where the values of skewness coefficients ranged between (± 3), which indicates that the research sample falls under the equilibrium curve in all variables under consideration.
The researcher also found parity between the two research groups (experimental - control), so as to ensure the equality of the two groups in all the variables under consideration.