diff --git a/api/serializers/gebruiker.py b/api/serializers/gebruiker.py
index 7dee6cdf..1292e010 100644
--- a/api/serializers/gebruiker.py
+++ b/api/serializers/gebruiker.py
@@ -2,6 +2,7 @@
 from api.models.gebruiker import Gebruiker
 from api.models.vak import Vak
 
+
 class GebruikerSerializer(serializers.ModelSerializer):
     """
     Serializer voor het serialiseren en deserialiseren van Gebruiker objecten.
@@ -16,13 +17,13 @@ class GebruikerSerializer(serializers.ModelSerializer):
         update(self, instance, validated_data): Werkt een bestaande gebruiker bij in de database.
     """
 
-    first_name = serializers.CharField(source='user.first_name', read_only=True)
-    last_name = serializers.CharField(source='user.last_name', read_only=True)
-    email = serializers.EmailField(source='user.email', read_only=True)
+    first_name = serializers.CharField(source="user.first_name", read_only=True)
+    last_name = serializers.CharField(source="user.last_name", read_only=True)
+    email = serializers.EmailField(source="user.email", read_only=True)
 
     class Meta:
         model = Gebruiker
-        fields = ['user', 'is_lesgever', 'first_name', 'last_name', 'email']
+        fields = ["user", "is_lesgever", "first_name", "last_name", "email"]
 
     def create(self, validated_data):
         """
@@ -52,8 +53,13 @@ def update(self, instance, validated_data):
         instance.save()
         return instance
 
+
 def validate_lesgever_change(instance):
     if instance.is_lesgever and Vak.objects.filter(lesgevers=instance):
-        raise serializers.ValidationError(f"De lesgever {instance} moet eerst verwijderd worden als lesgever in zijn huidige vakken")
+        raise serializers.ValidationError(
+            f"De lesgever {instance} moet eerst verwijderd worden als lesgever in zijn huidige vakken"
+        )
     elif not instance.is_lesgever and Vak.objects.filter(studenten=instance):
-        raise serializers.ValidationError(f"De student {instance} moet eerst verwijderd worden als student in zijn huidige vakken")
\ No newline at end of file
+        raise serializers.ValidationError(
+            f"De student {instance} moet eerst verwijderd worden als student in zijn huidige vakken"
+        )
diff --git a/api/tests/factories/indiening.py b/api/tests/factories/indiening.py
index 38d63ece..457a0a1c 100644
--- a/api/tests/factories/indiening.py
+++ b/api/tests/factories/indiening.py
@@ -22,6 +22,11 @@ class Meta:
             fake.date_time_between(start_date="+1d", end_date="+30d")
         )
     )
+    status = factory.Faker("boolean")
+    
+    indiening_bestanden = factory.RelatedFactory(
+        "api.tests.factories.indiening.IndieningBestandFactory", "indiening"
+    )
 
 
 class IndieningBestandFactory(DjangoModelFactory):
diff --git a/api/tests/factories/project.py b/api/tests/factories/project.py
index 216d1998..19669fc5 100644
--- a/api/tests/factories/project.py
+++ b/api/tests/factories/project.py
@@ -23,4 +23,11 @@ class Meta:
             fake.date_time_between(start_date="+1d", end_date="+30d")
         )
     )
+    extra_deadline = factory.LazyFunction(
+        lambda: timezone.make_aware(
+            fake.date_time_between(start_date="+30d", end_date="+40d")
+        )
+    )
     max_score = factory.Faker("random_int", min=10, max=100)
+    zichtbaar = factory.Faker('boolean')
+    gearchiveerd = factory.Faker('boolean')
diff --git a/api/tests/models/test_indiening.py b/api/tests/models/test_indiening.py
index b3bd52a6..094c0f63 100644
--- a/api/tests/models/test_indiening.py
+++ b/api/tests/models/test_indiening.py
@@ -15,14 +15,12 @@ def test_groep(self):
 
     def test_tijdstip(self):
         self.assertIsNotNone(self.indiening.tijdstip)
-
-    def test_indiening_bestand(self):
-        self.assertEqual(self.indiening.indieningbestand_set.count(), 0)
-
-    def test_indiening_bestand_add(self):
-        IndieningBestandFactory.create(indiening=self.indiening)
-        self.assertEqual(self.indiening.indieningbestand_set.count(), 1)
-
+    
+    def test_status(self):
+        self.assertIsNotNone(self.indiening.status)
+    
+    def test_indiening_bestanden(self):
+        self.assertEqual(self.indiening.indiening_bestanden.count(), 1)
 
 class IndieningBestandModelTest(TestCase):
     def setUp(self):
diff --git a/api/tests/models/test_project.py b/api/tests/models/test_project.py
index 971c0eec..29ec4d61 100644
--- a/api/tests/models/test_project.py
+++ b/api/tests/models/test_project.py
@@ -14,3 +14,18 @@ def test_project_vak(self):
 
     def test_project_max_score(self):
         self.assertTrue(10 <= self.project.max_score <= 100)
+    
+    def test_project_zichtbaar(self):
+        self.assertIsNotNone(self.project.zichtbaar)
+    
+    def test_project_gearchiveerd(self):
+        self.assertIsNotNone(self.project.gearchiveerd)
+    
+    def test_project_deadline(self):
+        self.assertIsNotNone(self.project.deadline)
+    
+    def test_project_extra_deadline(self):
+        self.assertIsNotNone(self.project.extra_deadline)
+    
+    def test_project_opgave_bestand(self):
+        self.assertEqual(self.project.opgave_bestand.read(), b"file content")