diff --git a/src/main/java/HWLesson_9/Course.java b/src/main/java/HWLesson_9/Course.java
new file mode 100644
index 0000000..fb3f781
--- /dev/null
+++ b/src/main/java/HWLesson_9/Course.java
@@ -0,0 +1,38 @@
+package HWLesson_9;
+
+import java.text.MessageFormat;
+import java.util.Objects;
+
+public class Course {
+    private String name;
+
+    public Course(String name) {
+        this.name = name;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    @Override
+    public String toString() {
+        return MessageFormat.format("{0}", name);
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+        Course course = (Course) o;
+        return Objects.equals(name, course.name);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(name);
+    }
+}
diff --git a/src/main/java/HWLesson_9/Student.java b/src/main/java/HWLesson_9/Student.java
new file mode 100644
index 0000000..b05e575
--- /dev/null
+++ b/src/main/java/HWLesson_9/Student.java
@@ -0,0 +1,54 @@
+package HWLesson_9;
+
+import java.util.Collection;
+import java.util.List;
+import java.util.stream.Collectors;
+
+public class Student {
+    private String name;
+    private List<Course> courses;
+
+    public Student(String name, List<Course> courses) {
+        this.name = name;
+        this.courses = courses;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public List<Course> getCourses() {
+        return courses;
+    }
+
+    public void setCourses(List<Course> courses) {
+        this.courses = courses;
+    }
+
+    public static List<Course> getUniqueCourses(List<Student> students){
+        return students.stream()
+                .map(Student::getCourses)
+                .flatMap(Collection::stream)
+                .distinct()
+                .collect(Collectors.toList());
+    }
+
+    public static List<String> getListOfThirstyForKnowledgeStudent(List<Student> students, int quantity){
+        return students.stream()
+                .sorted((s1, s2) -> s2.getCourses().size() - s1.getCourses().size())
+                .limit(quantity)
+                .map(Student::getName)
+                .collect(Collectors.toList());
+    }
+
+    public static List<String> getListOfStudentVisitingCourse(List<Student> students, Course course){
+        return students.stream()
+                .filter((s) -> s.getCourses().contains(course))
+                .map(Student::getName)
+                .collect(Collectors.toList());
+    }
+}
diff --git a/src/main/java/HWLesson_9/Study.java b/src/main/java/HWLesson_9/Study.java
new file mode 100644
index 0000000..1cb268c
--- /dev/null
+++ b/src/main/java/HWLesson_9/Study.java
@@ -0,0 +1,46 @@
+package HWLesson_9;
+
+import java.util.Arrays;
+import java.util.List;
+import static HWLesson_9.Student.getListOfStudentVisitingCourse;
+import static HWLesson_9.Student.getListOfThirstyForKnowledgeStudent;
+import static HWLesson_9.Student.getUniqueCourses;
+
+public class Study {
+    public static void main(String[] args) {
+        List<Student> students = Arrays.asList(
+                new Student("Стеша",
+                        Arrays.asList(
+                                new Course("Физика"),
+                                new Course("Математическая логика"),
+                                new Course("Теория вероятности"),
+                                new Course("Аналитическая геометрия"),
+                                new Course("Мат. анализ")
+                        )),
+                new Student("Афанасий",
+                        Arrays.asList(
+                                new Course("Дискретная математика"),
+                                new Course("Математическая логика"),
+                                new Course("Аналитическая геометрия"),
+                                new Course("Мат. анализ")
+                        )),
+                new Student("Серафим",
+                        Arrays.asList(
+                                new Course("Теоретическая механика"),
+                                new Course("Аналитическая геометрия"),
+                                new Course("Мат. анализ")
+                        )),
+                new Student("Фекла",
+                        Arrays.asList(
+                                new Course("Аналитическая геометрия"),
+                                new Course("Мат. анализ")
+                        ))
+        );
+        Course mathLogic = new Course("Математическая логика");
+
+        System.out.println("Список уникальных курсов: " + getUniqueCourses(students));
+        System.out.println("Список трёх самых любознательных студентов: "
+                + getListOfThirstyForKnowledgeStudent(students, 3));
+        System.out.println("Список студентов, посещающих курс \"Математическая логика\": " + getListOfStudentVisitingCourse(students, mathLogic));
+    }
+}