The Current Study Aims At Exploring The Effect of Some Acts And Performances To Develop Skills of Systemic Thinking For Secondary Three Students, Literary Section, By Designing A Digital Course In Philosophy. The Study Sample Included (30) Students from Om Al Mo'mneen Literary Secondary School In Tanta-Egypt. As For Implementing The Research, An Overall Digital Course In Psychology Was Designed According To Systemic Thinking In The Light of Dynamically Related Parts Besides Analyzing The Course Into Elements Divided Into Units Leading To Forming Parts Which Are Lessons. So, The Course Was Formed of Units Containing Lessons Strongly Related To The Units. Lessons Contain Educational Goals Besides Educational Videos Covering And Explaining The Lessons Which Are Presented By Activities And Tasks Students Do. Moreover, Sessions of Systemic Thinking Were Designed To Discuss Four Basic Skills: Analyzing The Main Systems Into Subsidiary Ones, Understanding Relationships Between Elements Inside The System, Removing Gaps Between Elements Inside The System And Rebuilding Systems From Their Components. A Nine – Task Test Was Designed To Measure Skills of Systemic Thinking In Psychology. Every Task Is About A Complicated Situation In Which A Student Is Required To Embody Relationships Inside The Situation In A Flow Chart. Then, A Student Is Asked To Do A Multi-Choice Question. The Aim of That Test Is To Measure Student's Ability To Think About Topics Stated In The Digital Course Content of Psychology. Results Demonstrated Progress In Systemic Thinking During Cognitive Development For The Skills of The Digital Psychology Course