diff --git a/com.examples.exercise/src/main/java/com/examples/exercise/DbMongo.java b/com.examples.exercise/src/main/java/com/examples/exercise/DbMongo.java
index 0bdeb70..8cbbe2a 100644
--- a/com.examples.exercise/src/main/java/com/examples/exercise/DbMongo.java
+++ b/com.examples.exercise/src/main/java/com/examples/exercise/DbMongo.java
@@ -3,6 +3,7 @@
 import java.util.ArrayList;
 import java.util.List;
 
+import com.mongodb.BasicDBObject;
 import com.mongodb.DB;
 import com.mongodb.DBCollection;
 import com.mongodb.DBCursor;
@@ -33,11 +34,19 @@ public void updateDB(String id, String name) {
 	}
 
 	public boolean exists(String id) {
+		if (takeStudentsById(id) != null) {
+			return true;
+		}
 		return false;
 	}
 
 	public Student takeStudentsById(String id) {
-		return null;
+		BasicDBObject searchQuery = new BasicDBObject();
+		searchQuery.put("id", id);
+		DBObject toFind = students.findOne(searchQuery);
+		return toFind != null ? 
+				new Student((String) toFind.get("id"), (String) toFind.get("name")) : 
+					null;
 	}
 
 	public void add(Student student) {
diff --git a/com.examples.exercise/src/test/java/com/examples/exercise/DbMongoTest.java b/com.examples.exercise/src/test/java/com/examples/exercise/DbMongoTest.java
index 8ddbd12..03e56b0 100644
--- a/com.examples.exercise/src/test/java/com/examples/exercise/DbMongoTest.java
+++ b/com.examples.exercise/src/test/java/com/examples/exercise/DbMongoTest.java
@@ -37,13 +37,34 @@ public void testGetAllStudentsEmpty() {
 	
 	@Test
 	public void testGetAllStudentsNotEmpty(){
-		BasicDBObject document = new BasicDBObject();
-		document.put("id", "1");
-		document.put("name", "first");
-		students.insert(document);
+		addStudent("1", "first");
 		assertEquals(1, database.getAllStudentsList().size());
 		assertEquals("1", database.getAllStudentsList().get(0).getId());
 		assertEquals("first", database.getAllStudentsList().get(0).getName());
 	}
 
+	private void addStudent(String id, String name) {
+		BasicDBObject document = new BasicDBObject();
+		document.put("id", id);
+		document.put("name", name);
+		students.insert(document);
+	}
+	
+	@Test
+	public void testGetStudentByIdNotFound(){
+		addStudent("1", "first");
+		assertNull(database.takeStudentsById("2"));
+	}
+	
+	@Test
+	public void testGetStudentByIdFound(){
+		addStudent("1", "first");
+		Student found = database.takeStudentsById("1");
+		assertNotNull(found);
+		assertEquals("1", found.getId());
+		assertEquals("first", found.getName());
+	}
+
+	
 }
+