diff --git a/src/CourseRegistrationStarter/Course.java b/src/CourseRegistrationStarter/Course.java
index 7f13a14..6d9d4cb 100644
--- a/src/CourseRegistrationStarter/Course.java
+++ b/src/CourseRegistrationStarter/Course.java
@@ -4,6 +4,8 @@ public class Course {
     private String courseName;
     private String courseCode;
     private int capacity;
+    private boolean canDrop = false;
+
 
     public Course(String courseName, String courseCode, int capacity) {
         this.courseName = courseName;
@@ -23,6 +25,15 @@ public class Course {
         return capacity;
     }
 
+    public boolean isDropped() {
+        return canDrop;
+    }
+
+    public void setCanDrop(boolean canDrop) {
+        this.canDrop = canDrop;
+
+    }
+
     public boolean reduceCapacity() {
         if (capacity > 0) {
             capacity--;
@@ -34,4 +45,11 @@ public class Course {
     public void increaseCapacity() {
         capacity++;
     }
+
+    @Override
+    public String toString() {
+        return  courseName + " (" + courseCode + ") " + "remaining capacity : " + capacity;
+    }
+
 }
+
diff --git a/src/CourseRegistrationStarter/Main.java b/src/CourseRegistrationStarter/Main.java
index 8f06373..50389cc 100644
--- a/src/CourseRegistrationStarter/Main.java
+++ b/src/CourseRegistrationStarter/Main.java
@@ -1,5 +1,9 @@
 package CourseRegistrationStarter;
 
+import javax.lang.model.element.NestingKind;
+import java.util.Objects;
+import java.util.Scanner;
+
 public class Main {
     public static void main(String[] args) {
         // TODO:
@@ -10,5 +14,99 @@ public class Main {
         // 5. Register the student in some courses
         // 6. Drop one course
         // 7. Print the final registered course list
+
+        Course course1 = new Course("Advanced Programming", "AP1404", 2);
+
+        Course course2 = new Course("Data Structures", "DS140401", 3);
+
+        Course course3 = new Course("Database System", "DS140402", 1);
+
+        Course course4 = new Course("Math2", "M1404", 4);
+
+        Student myStudent = new Student("mohammadReza", "Reza404222");
+
+        RegistrationSystem mySystem = new RegistrationSystem();
+
+        mySystem.addCourseToSystem(course1);
+        mySystem.addCourseToSystem(course2);
+        mySystem.addCourseToSystem(course3);
+        mySystem.addCourseToSystem(course4);
+
+        Scanner scanner = new Scanner(System.in);
+
+        while (true) {
+
+            System.out.println("==== Course Registration Menu ====");
+            System.out.println("1.Show all courses");
+            System.out.println("2.Register course");
+            System.out.println("3.Drop course");
+            System.out.println("4.Show my courses");
+            System.out.println("5.Exit");
+            System.out.println("choose an option: ");
+
+            int choice = scanner.nextInt();
+            scanner.nextLine();
+
+            if (choice == 1) {
+
+                System.out.println("All courses on System: ");
+                mySystem.showAllCourses();
+
+            } else if (choice == 2) {
+
+                System.out.println("Enter course code to register: ");
+                String inputCode = scanner.nextLine();
+
+                Course selected = mySystem.findCourseByCode(inputCode);
+
+                if (selected == null) {
+
+                    System.out.println("this code in invalid");
+                } else if (selected.isDropped()) {
+
+                    System.out.println("you previously dropped this course and you can register again");
+                }
+                else if (myStudent.addCourse(selected) && selected.reduceCapacity()) {
+
+                    System.out.println("course " + selected.getCourseName() + " registered successfully");
+
+                } else {
+                    System.out.println("this course in full");
+                }
+
+            } else if (choice == 3) {
+
+                System.out.println("Enter course code to Drop it: ");
+                String inputCode = scanner.nextLine();
+
+                Course found = mySystem.findCourseByCode(inputCode);
+
+                if (found == null) {
+                    System.out.println("this course has not registered yet");
+                } else {
+                    if (myStudent.dropCourse(found)) {
+                        found.reduceCapacity();
+                        found.increaseCapacity();
+                        System.out.println("course dropped successfully");
+                    } else {
+                        System.out.println("you are not registered in this course");
+                    }
+                }
+
+
+            } else if (choice == 4) {
+
+                myStudent.showRegisteredCourses();
+
+            } else if (choice == 5) {
+
+                System.out.println("exiting...");
+                break;
+            }
+
+        }
+
+        scanner.close();
+
     }
 }
diff --git a/src/CourseRegistrationStarter/RegistrationSystem.java b/src/CourseRegistrationStarter/RegistrationSystem.java
index 934f222..07f3357 100644
--- a/src/CourseRegistrationStarter/RegistrationSystem.java
+++ b/src/CourseRegistrationStarter/RegistrationSystem.java
@@ -9,16 +9,23 @@ public class RegistrationSystem {
     }
 
     public void addCourseToSystem(Course c) {
-        // TODO: Add the course to the system
+        courses.add(c);
     }
 
     public Course findCourseByCode(String code) {
-        // TODO: Search for a course by course code
-        // Return the matching course if found, otherwise return null
+
+        for (Course c : courses) {
+            if (c.getCourseCode().equals(code))
+                return c;
+        }
+
         return null;
     }
 
     public void showAllCourses() {
-        // TODO: Print all courses in the system
+
+        for (Course c : courses) {
+            System.out.println(c);
+        }
     }
 }
diff --git a/src/CourseRegistrationStarter/Student.java b/src/CourseRegistrationStarter/Student.java
index 02c11d8..ed9780c 100644
--- a/src/CourseRegistrationStarter/Student.java
+++ b/src/CourseRegistrationStarter/Student.java
@@ -21,19 +21,36 @@ public class Student {
     }
 
     public boolean addCourse(Course c) {
-        // TODO: Register the student in the course if capacity allows
-        // Return true if registration was successful, otherwise false
-        return false;
+
+        if (c.getCapacity() > 0) {
+            registeredCourses.add(c);
+            return true;
+        }
+        else
+            return false;
     }
 
     public boolean dropCourse(Course c) {
-        // TODO: Remove the course from the student's list
-        // Restore the course capacity if removal was successful
-        // Return true if the course was dropped, otherwise false
+        for (Course a : registeredCourses) {
+            if(a.getCourseCode().equals(c.getCourseCode())) {
+                registeredCourses.remove(c);
+                c.setCanDrop(true);
+                return true;
+            }
+        }
         return false;
     }
 
     public void showRegisteredCourses() {
-        // TODO: Print all registered courses
+
+        if (registeredCourses.isEmpty()) {
+            System.out.println("you have not registered in any courses yet");
+            return;
+        }
+
+        System.out.println("your registered courses: ");
+        for (Course c : registeredCourses) {
+            System.out.println(c);
+        }
     }
 }
\ No newline at end of file