diff --git a/advlabdb/adminModelViews.py b/advlabdb/adminModelViews.py
index 1bac562..548de33 100644
--- a/advlabdb/adminModelViews.py
+++ b/advlabdb/adminModelViews.py
@@ -690,13 +690,10 @@ class ExperimentMarkView(SecureAdminModelView):
             blank_text="-",
         )
 
-        markChoices = [(-1, "-")] + list(zip(range(16)[::-1], range(16)[::-1]))
-
-        oral_mark = SelectField("Oral Mark", choices=markChoices, coerce=int)
-        protocol_mark = SelectField("Protocol Mark", choices=markChoices, coerce=int)
-
     form = CreateForm
 
+    can_edit = False
+
     column_descriptions = {
         "oral_mark": "Between 0 and 15",
         "protocol_mark": "Between 0 and 15",
@@ -731,35 +728,12 @@ class ExperimentMarkView(SecureAdminModelView):
         )
     """
 
-    def checkForm(form):
-        if form.oral_mark and form.oral_mark.data == -1:
-            form.oral_mark.data = None
-
-        if form.protocol_mark and form.protocol_mark.data == -1:
-            form.protocol_mark.data = None
-
-        return form
-
-    def create_model(self, form):
-        form = ExperimentMarkView.checkForm(form)
-
-        model = super().create_model(form)
-
-        if model and (model.oral_mark or model.protocol_mark):
-            try:
-                model.edited_by_admin = True
-
-                self.session.commit()
-            except Exception as ex:
-                flash(str(ex), "error")
-
-                self.session.rollback()
-
-        return model
+    def customCreateModel(self, form):
+        return ExperimentMark.customInit(
+            part_student=form.part_student.data, group_experiment=form.group_experiment.data
+        )
 
     def update_model(self, form, model):
-        form = ExperimentMarkView.checkForm(form)
-
         if (form.oral_mark and form.oral_mark.data != model.oral_mark) or (
             form.protocol_mark and form.protocol_mark.data != model.protocol_mark
         ):
diff --git a/advlabdb/models.py b/advlabdb/models.py
index 84d09c9..6e00f72 100644
--- a/advlabdb/models.py
+++ b/advlabdb/models.py
@@ -294,7 +294,7 @@ class Appointment(db.Model):
         semesterExperimentAssistants = semesterExperiment.assistants
 
         if not semesterExperimentAssistants:
-            raise Exception(f"{semesterExperiment} has no assistants yet!")
+            raise Exception(f"{semesterExperiment} does not have assistants yet!")
 
         if assistant:
             if assistant not in semesterExperimentAssistants:
@@ -423,6 +423,15 @@ class ExperimentMark(db.Model):
 
     __table_args__ = (db.UniqueConstraint(part_student_id, group_experiment_id),)
 
+    def customInit(part_student, group_experiment):
+        if not part_student.group:
+            raise DataBaseException("The part student does not have a group yet!")
+        else:
+            if group_experiment not in part_student.group.group_experiments:
+                raise DataBaseException("The group of the part student does not have the given group experiment!")
+
+        return ExperimentMark(part_student=part_student, group_experiment=group_experiment)
+
     def repr(self):
         return f"Oral {self.oral_mark}; Prot {self.protocol_mark}"