diff --git a/advlabdb/modelViews.py b/advlabdb/modelViews.py
index 37f4511..ed7b121 100644
--- a/advlabdb/modelViews.py
+++ b/advlabdb/modelViews.py
@@ -187,9 +187,27 @@ class PartStudentModelView(SecureModelView):
     form_excluded_columns = ["experiment_marks"]
 
 
+class GroupModelView(SecureModelView):
+    partsLabels = getConfig("partsLabels")
+    column_filters = [PartFilter(Group.part_id, "Part", options=list(zip(partsLabels, partsLabels)))]
+
+    def validate_form(self, form):
+        if request.method == "POST":
+            if Group.query.filter(Group.number == form.number.data, Group.part == form.part.data).first():
+                lastTakenGroupNumber = (
+                    Group.query.filter(Group.part == form.part.data).order_by(Group.number)[-1].number
+                )
+                flash(
+                    f"Group number taken in this part! Last group number taken in this part is {lastTakenGroupNumber}.",
+                    "warning",
+                )
+                return False
+        return super().validate_form(form)
+
+
 admin.add_view(StudentModelView(Student, db.session))
 admin.add_view(PartStudentModelView(PartStudent, db.session))
-admin.add_view(SecureModelView(Group, db.session))
+admin.add_view(GroupModelView(Group, db.session))
 admin.add_view(SecureModelView(GroupExperiment, db.session))
 admin.add_view(SecureModelView(Experiment, db.session))
 admin.add_view(SecureModelView(PartExperiment, db.session))
diff --git a/advlabdb/utils.py b/advlabdb/utils.py
index c18ad4f..124556e 100644
--- a/advlabdb/utils.py
+++ b/advlabdb/utils.py
@@ -99,7 +99,6 @@ def partFromLabelInUserActiveSemester(partLabel):
     for part in userActiveSemester().parts:
         if part.label == partLabel:
             return part
-    return False
 
 
 def setActiveSemester(semesterId):