diff --git a/src/main/java/com/github/curriculeon/Classroom.java b/src/main/java/com/github/curriculeon/Classroom.java
new file mode 100644
index 0000000..6b1a8c9
--- /dev/null
+++ b/src/main/java/com/github/curriculeon/Classroom.java
@@ -0,0 +1,35 @@
+package com.github.curriculeon;
+
+import java.util.HashMap;
+import java.util.Map;
+
+public enum Classroom {
+    INSTANCE;
+    private Students students = Students.getInstance();
+    private Instructors instructors = Instructors.getInstance();
+
+    private Classroom() {
+        students = Students.getInstance();
+        instructors = Instructors.getInstance();
+    }
+
+    public void hostLecture(Teacher teacher, double numberOfHours) {
+        teacher.lecture(students.toArray(), numberOfHours);
+    }
+
+    public void hostLecture(long id, double numberOfHours) {
+        hostLecture(instructors.findById(id), numberOfHours);
+    }
+
+    public Map<Student, Double> getStudyMap() {
+        Map<Student, Double> studentTotalTimeMap = new HashMap<>();
+        for (Student currentStudent : students.toArray()) {
+             studentTotalTimeMap.put(currentStudent, currentStudent.getTotalStudyTime());
+        }
+        return studentTotalTimeMap;
+    }
+
+    public static Classroom getInstance() {
+        return INSTANCE;
+    }
+}
diff --git a/src/main/java/com/github/curriculeon/Educator.java b/src/main/java/com/github/curriculeon/Educator.java
new file mode 100644
index 0000000..dfd44d1
--- /dev/null
+++ b/src/main/java/com/github/curriculeon/Educator.java
@@ -0,0 +1,28 @@
+package com.github.curriculeon;
+
+public enum Educator implements Teacher {
+    LEON,
+    HASSEB;
+
+    private double hoursWorked;
+    private final Instructor instructor;
+
+    Educator() {
+        long id = this.ordinal();
+        String name = this.name();
+        this.instructor = new Instructor(id, name);
+        Instructors.getInstance().add(instructor);
+    }
+
+    @Override
+    public void teach(Learner learner, double numberOfHours) {
+        instructor.teach(learner, numberOfHours);
+        hoursWorked += numberOfHours;
+    }
+
+    @Override
+    public void lecture(Learner[] learners, double numberOfHours) {
+        instructor.lecture(learners, numberOfHours);
+        hoursWorked += numberOfHours;
+    }
+}
diff --git a/src/main/java/com/github/curriculeon/Instructor.java b/src/main/java/com/github/curriculeon/Instructor.java
new file mode 100644
index 0000000..168c0ce
--- /dev/null
+++ b/src/main/java/com/github/curriculeon/Instructor.java
@@ -0,0 +1,23 @@
+package com.github.curriculeon;
+
+public class Instructor extends Person implements Teacher {
+
+    public Instructor() {
+        super();
+    }
+
+    public Instructor(Long id, String name) {
+        super(id, name);
+    }
+
+    @Override
+    public void teach(Learner learner, double numberOfHours) {
+        learner.learn(numberOfHours);
+    }
+
+    @Override
+    public void lecture(Learner[] learners, double numberOfHours) {
+        double numberOfHoursPerLearner = numberOfHours / learners.length;
+        for(Learner learner : learners) learner.learn(numberOfHoursPerLearner);
+    }
+}
diff --git a/src/main/java/com/github/curriculeon/Instructors.java b/src/main/java/com/github/curriculeon/Instructors.java
new file mode 100644
index 0000000..07ff603
--- /dev/null
+++ b/src/main/java/com/github/curriculeon/Instructors.java
@@ -0,0 +1,23 @@
+package com.github.curriculeon;
+
+public class Instructors extends  People<Instructor> {
+    public static Instructors INSTANCE = new Instructors();
+
+    private Instructors() {
+        this.add(new Instructor(0L, "Leon"));
+        this.add(new Instructor(1L, "Hasseb"));
+    }
+
+    @Override
+    public Instructor[] toArray() {
+        Instructor[] instructorList = new Instructor[this.count()];
+        for (int i = 0; i < instructorList.length; i++) {
+            instructorList[i] = this.findById(i);
+        }
+        return instructorList;
+    }
+
+    public static Instructors getInstance() {
+        return INSTANCE;
+    }
+}
diff --git a/src/main/java/com/github/curriculeon/Learner.java b/src/main/java/com/github/curriculeon/Learner.java
new file mode 100644
index 0000000..c69a07b
--- /dev/null
+++ b/src/main/java/com/github/curriculeon/Learner.java
@@ -0,0 +1,6 @@
+package com.github.curriculeon;
+
+public interface Learner {
+    void learn(double numberOfHours);
+    Double getTotalStudyTime();
+}
diff --git a/src/main/java/com/github/curriculeon/People.java b/src/main/java/com/github/curriculeon/People.java
new file mode 100644
index 0000000..188489e
--- /dev/null
+++ b/src/main/java/com/github/curriculeon/People.java
@@ -0,0 +1,52 @@
+package com.github.curriculeon;
+
+import java.util.ArrayList;
+import java.util.Iterator;
+import java.util.List;
+
+public abstract class People<E extends Person> implements Iterable<E> {
+    private List<E> list;
+
+    public People() {
+        list = new ArrayList<>();
+    }
+
+    public void add(E e) {
+        list.add(e);
+    }
+
+    public E findById(long id) {
+        E found = null;
+        for(E e : list) {
+            if(e.getId() == id) found = e;
+        }
+        return found;
+    }
+
+    public boolean contains(E e) {
+        return list.contains(e);
+    }
+
+    public void remove(E e) {
+        list.remove(e);
+    }
+
+    public void remove(long id) {
+        list.remove(findById(id));
+    }
+
+    public void removeAll() {
+        list.clear();
+    }
+
+    public int count() {
+        return list.size();
+    }
+
+    public abstract E[] toArray();
+
+    @Override
+    public Iterator<E> iterator() {
+        return list.iterator();
+    }
+}
diff --git a/src/main/java/com/github/curriculeon/Person.java b/src/main/java/com/github/curriculeon/Person.java
index 3c8350b..317c7af 100644
--- a/src/main/java/com/github/curriculeon/Person.java
+++ b/src/main/java/com/github/curriculeon/Person.java
@@ -1,5 +1,27 @@
 package com.github.curriculeon;
 
 public class Person {
+    private final long id;
+    private String name;
 
+    public Person() {
+        this(0, "");
+    }
+
+    public Person(long id, String name) {
+        this.id = id;
+        this.name = name;
+    }
+
+    public long getId() {
+        return id;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
 }
diff --git a/src/main/java/com/github/curriculeon/Student.java b/src/main/java/com/github/curriculeon/Student.java
new file mode 100644
index 0000000..91c9061
--- /dev/null
+++ b/src/main/java/com/github/curriculeon/Student.java
@@ -0,0 +1,23 @@
+package com.github.curriculeon;
+
+public class Student extends Person implements Learner {
+    private double totalStudyTime;
+
+    public Student() {
+        super();
+    }
+
+    public Student(Long id, String name) {
+        super(id, name);
+    }
+
+    @Override
+    public void learn(double numberOfHours) {
+        totalStudyTime += numberOfHours;
+    }
+
+    @Override
+    public Double getTotalStudyTime() {
+        return totalStudyTime;
+    }
+}
diff --git a/src/main/java/com/github/curriculeon/Students.java b/src/main/java/com/github/curriculeon/Students.java
new file mode 100644
index 0000000..d19e17e
--- /dev/null
+++ b/src/main/java/com/github/curriculeon/Students.java
@@ -0,0 +1,28 @@
+package com.github.curriculeon;
+
+import java.time.Instant;
+import java.util.ArrayList;
+import java.util.List;
+
+public final class Students extends People<Student> {
+    private final static Students INSTANCE = new Students();
+
+    private Students() {
+        this.add(new Student(0L, "Lionel"));
+        this.add(new Student(1L, "Aita"));
+        this.add(new Student(2L, "Flagel"));
+    }
+
+    public static Students getInstance() {
+        return INSTANCE;
+    }
+
+    @Override
+    public Student[] toArray() {
+        Student[] studentList = new Student[this.count()];
+        for (int i = 0; i < studentList.length; i++) {
+            studentList[i] = this.findById(i);
+        }
+        return studentList;
+    }
+}
diff --git a/src/main/java/com/github/curriculeon/Teacher.java b/src/main/java/com/github/curriculeon/Teacher.java
new file mode 100644
index 0000000..2d9a34b
--- /dev/null
+++ b/src/main/java/com/github/curriculeon/Teacher.java
@@ -0,0 +1,6 @@
+package com.github.curriculeon;
+
+public interface Teacher {
+    void teach(Learner learner, double numberOfHours);
+    void lecture(Learner[] learners, double numberOfHours);
+}
diff --git a/src/test/java/com/github/curriculeon/TestClassroom.java b/src/test/java/com/github/curriculeon/TestClassroom.java
new file mode 100644
index 0000000..a275ecf
--- /dev/null
+++ b/src/test/java/com/github/curriculeon/TestClassroom.java
@@ -0,0 +1,28 @@
+package com.github.curriculeon;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+public class TestClassroom {
+    @Test
+    public void testHostLecture() {
+        //Given
+        Students students = Students.getInstance();
+        Instructors instructors = Instructors.getInstance();
+        Classroom classroom = Classroom.getInstance();
+
+        //When
+        classroom.hostLecture((Teacher)instructors.findById(0), 30);
+        classroom.hostLecture((Teacher)instructors.findById(0), 60);
+        classroom.hostLecture((Teacher)instructors.findById(1), 36);
+        classroom.hostLecture((Teacher)instructors.findById(1), 66);
+
+        //Then
+        for (Student student : (Student[]) students.toArray()) {
+            double expectedStudyTime = student.getTotalStudyTime();
+            double actualStudyTime = classroom.getStudyMap().get(student);
+            System.out.printf("Expecting studying time for student %d: %s\n", student.getId(), expectedStudyTime);
+            Assert.assertEquals(expectedStudyTime, actualStudyTime, 0.1);
+        }
+    }
+}
diff --git a/src/test/java/com/github/curriculeon/TestInstructor.java b/src/test/java/com/github/curriculeon/TestInstructor.java
new file mode 100644
index 0000000..945cfb8
--- /dev/null
+++ b/src/test/java/com/github/curriculeon/TestInstructor.java
@@ -0,0 +1,58 @@
+package com.github.curriculeon;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+public class TestInstructor {
+
+    @Test
+    public void testImplementation() {
+        Instructor instructor = new Instructor();
+        Assert.assertTrue(instructor instanceof Teacher);
+    }
+
+    @Test
+    public void testInheritance() {
+        Instructor instructor = new Instructor();
+        Assert.assertTrue(instructor instanceof Person);
+    }
+
+    @Test
+    public void testTeach() {
+        //Given
+        Instructor instructor = new Instructor();
+        Learner student = new Student();
+        double expectedNumberOfHours = 2.14;
+
+        //When
+        instructor.teach(student, expectedNumberOfHours);
+        double actualNumberOfHours = student.getTotalStudyTime();
+
+        //Then
+        Assert.assertEquals(expectedNumberOfHours, actualNumberOfHours, 0.1);
+    }
+
+    @Test
+    public void testLecture() {
+        //Given
+        Instructor instructor = new Instructor();
+        Learner student1 = new Student();
+        Learner student2 = new Student();
+        Learner student3 = new Student();
+        Learner student4 = new Student();
+        Learner student5 = new Student();
+
+        Learner[] learners = {student1, student2, student3, student4, student5};
+        double TotalNumberOfHours = 10.0;
+        double expectedNumberOfHoursPerLearner = 10.0/learners.length;
+
+        //When
+        instructor.lecture(learners, TotalNumberOfHours);
+
+        //Then
+        for(Learner student : learners)
+            Assert.assertEquals(expectedNumberOfHoursPerLearner, student.getTotalStudyTime(), 0.1);
+    }
+
+
+}
diff --git a/src/test/java/com/github/curriculeon/TestInstructors.java b/src/test/java/com/github/curriculeon/TestInstructors.java
new file mode 100644
index 0000000..322751c
--- /dev/null
+++ b/src/test/java/com/github/curriculeon/TestInstructors.java
@@ -0,0 +1,18 @@
+package com.github.curriculeon;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+public class TestInstructors {
+    @Test
+    public void test() {
+        //Given
+        Instructors instance = Instructors.getInstance();
+
+        //When
+        //Then
+        for(int i = 0; i < instance.count(); i++) {
+            Assert.assertTrue(instance.findById(i) instanceof Instructor);
+        }
+    }
+}
diff --git a/src/test/java/com/github/curriculeon/TestPeople.java b/src/test/java/com/github/curriculeon/TestPeople.java
new file mode 100644
index 0000000..8795e74
--- /dev/null
+++ b/src/test/java/com/github/curriculeon/TestPeople.java
@@ -0,0 +1,58 @@
+package com.github.curriculeon;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+public class TestPeople {
+
+    @Test
+    public void testAdd() {
+        //Given
+        Person person = new Person(234L, "Lionel");
+        People people = Instructors.getInstance();
+
+        //When
+        people.add(person);
+
+        //Then
+        Assert.assertTrue(people.contains(person));
+    }
+
+    @Test
+    public void testRemove() {
+        //Given
+        Person person1 = new Person(234L, "Lionel");
+        Person person2 = new Person(212L, "Ricky");
+        Person person3 = new Person(546L, "Bryan");
+        People people = Instructors.getInstance();
+
+        //When
+        people.add(person1);
+        people.add(person2);
+        people.add(person3);
+
+        people.remove(person2);
+
+        //Then
+        Assert.assertFalse(people.contains(person2));
+    }
+
+    @Test
+    public void testFindById() {
+        //Given
+        Person person1 = new Person(234L, "Lionel");
+        Person person2 = new Person(212L, "Ricky");
+        Person person3 = new Person(546L, "Bryan");
+        People people = Instructors.getInstance();
+
+        //When
+        people.add(person1);
+        people.add(person2);
+        people.add(person3);
+
+        //Then
+        for(Object person : people) Assert.assertTrue(people.contains(people.findById(((Person)person).getId())));
+    }
+
+
+}
diff --git a/src/test/java/com/github/curriculeon/TestPerson.java b/src/test/java/com/github/curriculeon/TestPerson.java
index 6c523fe..47cf238 100644
--- a/src/test/java/com/github/curriculeon/TestPerson.java
+++ b/src/test/java/com/github/curriculeon/TestPerson.java
@@ -1,5 +1,72 @@
 package com.github.curriculeon;
 
+import org.junit.Assert;
+import org.junit.Test;
+
 public class TestPerson {
+    private void testConstructor(long expectedId, String expectedName) {
+        Person person = new Person(expectedId, expectedName);
+        long actualId = person.getId();
+        String actualName = person.getName();
+        Assert.assertEquals(actualId, expectedId);
+        Assert.assertEquals(actualName, expectedName);
+    }
+
+    private void testSetName(String expectedName) {
+        Person person = new Person();
+        person.setName(expectedName);
+        String actualName = person.getName();
+        Assert.assertEquals(actualName, expectedName);
+    }
+
+    @Test
+     public void testConstructor0() {
+        testConstructor(0, null);
+    }
+
+    @Test
+    public void testConstructor1() {
+        testConstructor(234122, "Johnny");
+    }
+
+    @Test
+    public void testConstructor2() {
+        testConstructor(3260, "Zack");
+    }
+
+    @Test
+    public void testConstructor3() {
+        testConstructor(1, "Dona");
+    }
+
+    @Test
+    public void testConstructor4() {
+        testConstructor(4320, "Ryan");
+    }
+
+    @Test
+    public void testSetName0() {
+        testSetName(null);
+    }
+
+    @Test
+    public void testSetName1() {
+        testSetName("Tom");
+    }
+
+    @Test
+    public void testSetName2() {
+        testSetName("Jerry");
+    }
+
+    @Test
+    public void testSetName3() {
+        testSetName("Mack");
+    }
+
+    @Test
+    public void testSetName4() {
+        testSetName("Alan");
+    }
 
 }
diff --git a/src/test/java/com/github/curriculeon/TestStudent.java b/src/test/java/com/github/curriculeon/TestStudent.java
new file mode 100644
index 0000000..af1d16d
--- /dev/null
+++ b/src/test/java/com/github/curriculeon/TestStudent.java
@@ -0,0 +1,31 @@
+package com.github.curriculeon;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+public class TestStudent {
+
+    @Test
+    public void testImplementation() {
+        Student student = new Student();
+        Assert.assertTrue(student instanceof Learner);
+    }
+
+    @Test
+    public void testInheritance() {
+        Student student = new Student();
+        Assert.assertTrue(student instanceof Person);
+    }
+
+    @Test
+    public void testLearn() {
+        Student student = new Student();
+        double expectedNumberOfHours = 2.5;
+        student.learn(expectedNumberOfHours);
+        double actualNumberOfHours = student.getTotalStudyTime();
+        Assert.assertEquals(expectedNumberOfHours, actualNumberOfHours, 0.1);
+
+    }
+
+
+}
diff --git a/src/test/java/com/github/curriculeon/TestStudents.java b/src/test/java/com/github/curriculeon/TestStudents.java
new file mode 100644
index 0000000..6153e33
--- /dev/null
+++ b/src/test/java/com/github/curriculeon/TestStudents.java
@@ -0,0 +1,17 @@
+package com.github.curriculeon;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+public class TestStudents {
+    @Test
+    public void test() {
+        // Given
+        Students instance = Students.getInstance();
+
+        //Then
+        for(int i = 0; i < instance.count(); i++) {
+            Assert.assertTrue(instance.findById(i) instanceof Student);
+        }
+    }
+}