diff --git a/apps/participation/forms.py b/apps/participation/forms.py
index 47220a6..605601c 100644
--- a/apps/participation/forms.py
+++ b/apps/participation/forms.py
@@ -2,7 +2,7 @@ import re
 
 from bootstrap_datepicker_plus import DateTimePickerInput
 from django import forms
-from django.core.exceptions import ValidationError
+from django.core.exceptions import ObjectDoesNotExist, ValidationError
 from django.db.models import Q
 from django.utils.translation import gettext_lazy as _
 
@@ -128,7 +128,7 @@ class SendParticipationForm(forms.ModelForm):
         super().__init__(*args, **kwargs)
         try:
             self.fields["sent_participation"].initial = self.instance.sent_participation
-        except:     # No sent participation
+        except ObjectDoesNotExist:     # No sent participation
             pass
         self.fields["sent_participation"].queryset = Participation.objects.filter(
             ~Q(pk=self.instance.pk) & Q(problem=self.instance.problem, valid=True)
@@ -155,6 +155,11 @@ class QuestionForm(forms.ModelForm):
         super().__init__(*args, **kwargs)
         self.fields["question"].widget.attrs.update({"placeholder": _("How did you get the idea to ...?")})
 
+    def clean(self):
+        if Phase.current_phase().phase_number != 2:
+            self.add_error(None, _("You can only create or update a question during the second phase."))
+        return super().clean()
+
     class Meta:
         model = Question
         fields = ('question',)
diff --git a/apps/participation/tests.py b/apps/participation/tests.py
index 59a20be..4ce5822 100644
--- a/apps/participation/tests.py
+++ b/apps/participation/tests.py
@@ -4,7 +4,6 @@ from django.contrib.auth.models import User
 from django.contrib.contenttypes.models import ContentType
 from django.contrib.sites.models import Site
 from django.core.management import call_command
-from django.db.models import F
 from django.test import TestCase
 from django.urls import reverse
 from django.utils import timezone
@@ -504,6 +503,70 @@ class TestStudentParticipation(TestCase):
                                     data=dict(link="https://youtube.com/watch?v=73nsrixx7eI"))
         self.assertEqual(response.status_code, 200)
 
+    def test_questions(self):
+        """
+        Ensure that creating/updating/deleting a question is working.
+        """
+        self.user.registration.team = self.team
+        self.user.registration.save()
+
+        self.team.participation.valid = True
+        self.team.participation.save()
+
+        response = self.client.get(reverse("participation:add_question", args=(self.team.participation.pk,)))
+        self.assertEqual(response.status_code, 200)
+
+        # We are not in second phase
+        response = self.client.post(reverse("participation:add_question", args=(self.team.participation.pk,)),
+                                    data=dict(question="I got censored!"))
+        self.assertEqual(response.status_code, 200)
+
+        # Set the second phase
+        for i in range(1, 5):
+            Phase.objects.filter(phase_number=i).update(start=timezone.now() + timedelta(days=i - 2),
+                                                        end=timezone.now() + timedelta(days=i - 1))
+        self.assertEqual(Phase.current_phase().phase_number, 2)
+
+        # Create a question
+        response = self.client.post(reverse("participation:add_question", args=(self.team.participation.pk,)),
+                                    data=dict(question="I asked a question!"))
+        self.assertRedirects(response, reverse("participation:participation_detail",
+                                               args=(self.team.participation.pk,)), 302, 200)
+        qs = Question.objects.filter(participation=self.team.participation, question="I asked a question!")
+        self.assertTrue(qs.exists())
+        question = qs.get()
+
+        # Update a question
+        response = self.client.get(reverse("participation:update_question", args=(question.pk,)))
+        self.assertEqual(response.status_code, 200)
+        response = self.client.post(reverse("participation:update_question", args=(question.pk,)), data=dict(
+            question="The question changed!",
+        ))
+        self.assertRedirects(response, reverse("participation:participation_detail",
+                                               args=(self.team.participation.pk,)), 302, 200)
+        question.refresh_from_db()
+        self.assertEqual(question.question, "The question changed!")
+
+        # Delete the question
+        response = self.client.get(reverse("participation:delete_question", args=(question.pk,)))
+        self.assertEqual(response.status_code, 200)
+        response = self.client.post(reverse("participation:delete_question", args=(question.pk,)))
+        self.assertRedirects(response, reverse("participation:participation_detail",
+                                               args=(self.team.participation.pk,)), 302, 200)
+        self.assertFalse(Question.objects.filter(pk=question.pk).exists())
+
+        # Non-authenticated users are redirected to login page
+        self.client.logout()
+        response = self.client.get(reverse("participation:add_question", args=(self.team.participation.pk,)))
+        self.assertRedirects(response, reverse("login") + "?next=" +
+                             reverse("participation:add_question", args=(self.team.participation.pk,)), 302, 200)
+        response = self.client.get(reverse("participation:update_question", args=(self.question.pk,)))
+        self.assertRedirects(response, reverse("login") + "?next=" +
+                             reverse("participation:delete_question", args=(self.question.pk,)), 302, 200)
+        response = self.client.get(reverse("participation:add_question", args=(self.question.pk,)))
+        self.assertRedirects(response, reverse("login") + "?next=" +
+                             reverse("participation:add_question", args=(self.question.pk,)), 302, 200)
+
     def test_current_phase(self):
         """
         Ensure that the current phase is the good one.
diff --git a/apps/participation/views.py b/apps/participation/views.py
index 04a8455..de74762 100644
--- a/apps/participation/views.py
+++ b/apps/participation/views.py
@@ -418,6 +418,7 @@ class CreateQuestionView(LoginRequiredMixin, CreateView):
         self.participation = Participation.objects.get(pk=kwargs["pk"])
         if request.user.registration.is_admin or \
                 request.user.registration.participates and \
+                self.participation.valid and \
                 request.user.registration.team.pk == self.participation.team_id:
             return super().dispatch(request, *args, **kwargs)
         raise PermissionDenied
@@ -443,6 +444,7 @@ class UpdateQuestionView(LoginRequiredMixin, UpdateView):
             return self.handle_no_permission()
         if request.user.registration.is_admin or \
                 request.user.registration.participates and \
+                self.object.participation.valid and \
                 request.user.registration.team.pk == self.object.participation.team_id:
             return super().dispatch(request, *args, **kwargs)
         raise PermissionDenied
@@ -464,6 +466,7 @@ class DeleteQuestionView(LoginRequiredMixin, DeleteView):
             return self.handle_no_permission()
         if request.user.registration.is_admin or \
                 request.user.registration.participates and \
+                self.object.participation.valid and \
                 request.user.registration.team.pk == self.object.participation.team_id:
             return super().dispatch(request, *args, **kwargs)
         raise PermissionDenied
diff --git a/locale/fr/LC_MESSAGES/django.po b/locale/fr/LC_MESSAGES/django.po
index 3411a2a..a759138 100644
--- a/locale/fr/LC_MESSAGES/django.po
+++ b/locale/fr/LC_MESSAGES/django.po
@@ -7,7 +7,7 @@ msgid ""
 msgstr ""
 "Project-Id-Version: Corres2math\n"
 "Report-Msgid-Bugs-To: \n"
-"POT-Creation-Date: 2020-11-02 10:56+0100\n"
+"POT-Creation-Date: 2020-11-03 17:32+0100\n"
 "PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n"
 "Last-Translator: Yohann D'ANELLO <yohann.danello@animath.fr>\n"
 "Language-Team: LANGUAGE <LL@li.org>\n"
@@ -30,7 +30,7 @@ msgid "This task failed successfully."
 msgstr "Cette tâche a échoué avec succès."
 
 #: apps/eastereggs/templates/eastereggs/xp_modal.html:16
-#: templates/base_modal.html:19
+#: corres2math/templates/base_modal.html:19
 msgid "Close"
 msgstr "Fermer"
 
@@ -99,6 +99,16 @@ msgstr "changelogs"
 msgid "Changelog of type \"{action}\" for model {model} at {timestamp}"
 msgstr "Changelog de type \"{action}\" pour le modèle {model} le {timestamp}"
 
+#: apps/participation/admin.py:16 apps/participation/models.py:122
+#: apps/participation/tables.py:35 apps/participation/tables.py:62
+msgid "problem number"
+msgstr "numéro de problème"
+
+#: apps/participation/admin.py:21 apps/participation/models.py:128
+#: apps/participation/models.py:182
+msgid "valid"
+msgstr "valide"
+
 #: apps/participation/forms.py:20 apps/participation/models.py:33
 msgid "The trigram must be composed of three uppercase letters."
 msgstr "Le trigramme doit être composé de trois lettres majuscules."
@@ -123,19 +133,25 @@ msgstr "Vous ne pouvez pas envoyer de vidéo après la date limite."
 msgid "Send to team"
 msgstr "Envoyer à l'équipe"
 
-#: apps/participation/forms.py:152
+#: apps/participation/forms.py:156
 msgid "How did you get the idea to ...?"
 msgstr "Comment avez-vous eu l'idée de ... ?"
 
-#: apps/participation/forms.py:175
+#: apps/participation/forms.py:160
+msgid "You can only create or update a question during the second phase."
+msgstr ""
+"Vous pouvez créer ou modifier une question seulement pendant la seconde "
+"phase."
+
+#: apps/participation/forms.py:186
 msgid "Start date must be before the end date."
 msgstr "La date de début doit être avant la date de fin."
 
-#: apps/participation/forms.py:177
+#: apps/participation/forms.py:188
 msgid "This phase must start after the previous phases."
 msgstr "Cette phase doit commencer après les phases précédentes."
 
-#: apps/participation/forms.py:179
+#: apps/participation/forms.py:190
 msgid "This phase must end after the next phases."
 msgstr "Cette phase doit finir avant les phases suivantes."
 
@@ -187,15 +203,6 @@ msgstr "équipes"
 msgid "Problem #{problem:d}"
 msgstr "Problème n°{problem:d}"
 
-#: apps/participation/models.py:122 apps/participation/tables.py:35
-#: apps/participation/tables.py:62
-msgid "problem number"
-msgstr "numéro de problème"
-
-#: apps/participation/models.py:128 apps/participation/models.py:182
-msgid "valid"
-msgstr "valide"
-
 #: apps/participation/models.py:129 apps/participation/models.py:183
 msgid "The video got the validation of the administrators."
 msgstr "La vidéo a été validée par les administrateurs."
@@ -283,12 +290,12 @@ msgid "phases"
 msgstr "phases"
 
 #: apps/participation/templates/participation/create_team.html:11
-#: templates/base.html:231
+#: corres2math/templates/base.html:231
 msgid "Create"
 msgstr "Créer"
 
 #: apps/participation/templates/participation/join_team.html:11
-#: templates/base.html:227
+#: corres2math/templates/base.html:227
 msgid "Join"
 msgstr "Rejoindre"
 
@@ -462,7 +469,7 @@ msgstr "Définir l'équipe qui recevra votre vidéo"
 
 #: apps/participation/templates/participation/participation_detail.html:181
 #: apps/participation/templates/participation/participation_detail.html:233
-#: apps/participation/views.py:463
+#: apps/participation/views.py:482
 msgid "Upload video"
 msgstr "Envoyer la vidéo"
 
@@ -497,7 +504,7 @@ msgid "Update question"
 msgstr "Modifier la question"
 
 #: apps/participation/templates/participation/participation_detail.html:217
-#: apps/participation/views.py:440
+#: apps/participation/views.py:459
 msgid "Delete question"
 msgstr "Supprimer la question"
 
@@ -507,8 +514,8 @@ msgid "Display synthesis"
 msgstr "Afficher la synthèse"
 
 #: apps/participation/templates/participation/phase_list.html:10
-#: apps/participation/views.py:482 templates/base.html:68
-#: templates/base.html:70 templates/base.html:217
+#: apps/participation/views.py:501 corres2math/templates/base.html:68
+#: corres2math/templates/base.html:70 corres2math/templates/base.html:217
 msgid "Calendar"
 msgstr "Calendrier"
 
@@ -620,7 +627,7 @@ msgid "Update team"
 msgstr "Modifier l'équipe"
 
 #: apps/participation/templates/participation/team_detail.html:127
-#: apps/participation/views.py:296
+#: apps/participation/views.py:314
 msgid "Leave team"
 msgstr "Quitter l'équipe"
 
@@ -628,8 +635,8 @@ msgstr "Quitter l'équipe"
 msgid "Are you sure that you want to leave this team?"
 msgstr "Êtes-vous sûr·e de vouloir quitter cette équipe ?"
 
-#: apps/participation/views.py:36 templates/base.html:77
-#: templates/base.html:230
+#: apps/participation/views.py:36 corres2math/templates/base.html:77
+#: corres2math/templates/base.html:230
 msgid "Create team"
 msgstr "Créer une équipe"
 
@@ -641,80 +648,89 @@ msgstr "Vous ne participez pas, vous ne pouvez pas créer d'équipe."
 msgid "You are already in a team."
 msgstr "Vous êtes déjà dans une équipe."
 
-#: apps/participation/views.py:82 templates/base.html:82
-#: templates/base.html:226
+#: apps/participation/views.py:82 corres2math/templates/base.html:82
+#: corres2math/templates/base.html:226
 msgid "Join team"
 msgstr "Rejoindre une équipe"
 
-#: apps/participation/views.py:133 apps/participation/views.py:302
-#: apps/participation/views.py:335
+#: apps/participation/views.py:133 apps/participation/views.py:320
+#: apps/participation/views.py:353
 msgid "You are not in a team."
 msgstr "Vous n'êtes pas dans une équipe."
 
-#: apps/participation/views.py:134 apps/participation/views.py:336
+#: apps/participation/views.py:134 apps/participation/views.py:354
 msgid "You don't participate, so you don't have any team."
 msgstr "Vous ne participez pas, vous n'avez donc pas d'équipe."
 
-#: apps/participation/views.py:155
+#: apps/participation/views.py:156
 #, python-brace-format
 msgid "Detail of team {trigram}"
 msgstr "Détails de l'équipe {trigram}"
 
-#: apps/participation/views.py:180
+#: apps/participation/views.py:188
 msgid "You don't participate, so you can't request the validation of the team."
 msgstr ""
 "Vous ne participez pas, vous ne pouvez pas demander la validation de "
 "l'équipe."
 
-#: apps/participation/views.py:183
+#: apps/participation/views.py:191
 msgid "The validation of the team is already done or pending."
 msgstr "La validation de l'équipe est déjà faite ou en cours."
 
-#: apps/participation/views.py:196
+#: apps/participation/views.py:194
+msgid ""
+"The team can't be validated: missing email address confirmations, photo "
+"authorizations, people or the chosen problem is not set."
+msgstr ""
+"L'équipe ne peut pas être validée : il manque soit les confirmations "
+"d'adresse e-mail, soit une autorisation parentale, soit des personnes soit "
+"le problème n'a pas été choisi."
+
+#: apps/participation/views.py:213
 msgid "You are not an administrator."
 msgstr "Vous n'êtes pas administrateur."
 
-#: apps/participation/views.py:199
+#: apps/participation/views.py:216
 msgid "This team has no pending validation."
 msgstr "L'équipe n'a pas de validation en attente."
 
-#: apps/participation/views.py:218
+#: apps/participation/views.py:235
 msgid "You must specify if you validate the registration or not."
 msgstr "Vous devez spécifier si vous validez l'inscription ou non."
 
-#: apps/participation/views.py:245
+#: apps/participation/views.py:263
 #, python-brace-format
 msgid "Update team {trigram}"
 msgstr "Mise à jour de l'équipe {trigram}"
 
-#: apps/participation/views.py:282 apps/registration/views.py:243
+#: apps/participation/views.py:300 apps/registration/views.py:243
 #, python-brace-format
 msgid "Photo authorization of {student}.{ext}"
 msgstr "Autorisation de droit à l'image de {student}.{ext}"
 
-#: apps/participation/views.py:286
+#: apps/participation/views.py:304
 #, python-brace-format
 msgid "Photo authorizations of team {trigram}.zip"
 msgstr "Autorisations de droit à l'image de l'équipe {trigram}.zip"
 
-#: apps/participation/views.py:304
+#: apps/participation/views.py:322
 msgid "The team is already validated or the validation is pending."
 msgstr "La validation de l'équipe est déjà faite ou en cours."
 
-#: apps/participation/views.py:348
+#: apps/participation/views.py:366
 msgid "The team is not validated yet."
 msgstr "L'équipe n'est pas encore validée."
 
-#: apps/participation/views.py:357
+#: apps/participation/views.py:376
 #, python-brace-format
 msgid "Participation of team {trigram}"
 msgstr "Participation de l'équipe {trigram}"
 
-#: apps/participation/views.py:394
+#: apps/participation/views.py:413
 msgid "Create question"
 msgstr "Créer une question"
 
-#: apps/participation/views.py:491
+#: apps/participation/views.py:510
 msgid "Calendar update"
 msgstr "Mise à jour du calendrier"
 
@@ -907,9 +923,11 @@ msgid "Your password has been set. You may go ahead and log in now."
 msgstr "Votre mot de passe a été changé. Vous pouvez désormais vous connecter."
 
 #: apps/registration/templates/registration/password_reset_complete.html:10
-#: templates/base.html:130 templates/base.html:221 templates/base.html:222
-#: templates/registration/login.html:7 templates/registration/login.html:8
-#: templates/registration/login.html:25
+#: corres2math/templates/base.html:130 corres2math/templates/base.html:221
+#: corres2math/templates/base.html:222
+#: corres2math/templates/registration/login.html:7
+#: corres2math/templates/registration/login.html:8
+#: corres2math/templates/registration/login.html:25
 msgid "Log in"
 msgstr "Connexion"
 
@@ -1082,11 +1100,11 @@ msgstr "Anglais"
 msgid "French"
 msgstr "Français"
 
-#: templates/400.html:6
+#: corres2math/templates/400.html:6
 msgid "Bad request"
 msgstr "Requête invalide"
 
-#: templates/400.html:7
+#: corres2math/templates/400.html:7
 msgid ""
 "Sorry, your request was bad. Don't know what could be wrong. An email has "
 "been sent to webmasters with the details of the error. You can now watch "
@@ -1096,23 +1114,23 @@ msgstr ""
 "email a été envoyé aux administrateurs avec les détails de l'erreur. Vous "
 "pouvez désormais retourner voir des vidéos."
 
-#: templates/403.html:6
+#: corres2math/templates/403.html:6
 msgid "Permission denied"
 msgstr "Permission refusée"
 
-#: templates/403.html:7
+#: corres2math/templates/403.html:7
 msgid "You don't have the right to perform this request."
 msgstr "Vous n'avez pas le droit d'effectuer cette requête."
 
-#: templates/403.html:10 templates/404.html:10
+#: corres2math/templates/403.html:10 corres2math/templates/404.html:10
 msgid "Exception message:"
 msgstr "Message d'erreur :"
 
-#: templates/404.html:6
+#: corres2math/templates/404.html:6
 msgid "Page not found"
 msgstr "Page non trouvée"
 
-#: templates/404.html:7
+#: corres2math/templates/404.html:7
 #, python-format
 msgid ""
 "The requested path <code>%(request_path)s</code> was not found on the server."
@@ -1120,11 +1138,11 @@ msgstr ""
 "Le chemin demandé <code>%(request_path)s</code> n'a pas été trouvé sur le "
 "serveur."
 
-#: templates/500.html:6
+#: corres2math/templates/500.html:6
 msgid "Server error"
 msgstr "Erreur du serveur"
 
-#: templates/500.html:7
+#: corres2math/templates/500.html:7
 msgid ""
 "Sorry, an error occurred when processing your request. An email has been "
 "sent to webmasters with the detail of the error, and this will be fixed "
@@ -1135,47 +1153,47 @@ msgstr ""
 "avec les détails de l'erreur. Vous pouvez désormais retourner voir des "
 "vidéos."
 
-#: templates/base.html:64
+#: corres2math/templates/base.html:64
 msgid "Home"
 msgstr "Accueil"
 
-#: templates/base.html:88
+#: corres2math/templates/base.html:88
 msgid "My team"
 msgstr "Mon équipe"
 
-#: templates/base.html:93
+#: corres2math/templates/base.html:93
 msgid "My participation"
 msgstr "Ma participation"
 
-#: templates/base.html:100
+#: corres2math/templates/base.html:100
 msgid "Chat"
 msgstr "Chat"
 
-#: templates/base.html:104
+#: corres2math/templates/base.html:104
 msgid "Administration"
 msgstr "Administration"
 
-#: templates/base.html:112
+#: corres2math/templates/base.html:112
 msgid "Search..."
 msgstr "Chercher ..."
 
-#: templates/base.html:121
+#: corres2math/templates/base.html:121
 msgid "Return to admin view"
 msgstr "Retourner à l'interface administrateur"
 
-#: templates/base.html:126
+#: corres2math/templates/base.html:126
 msgid "Register"
 msgstr "S'inscrire"
 
-#: templates/base.html:142
+#: corres2math/templates/base.html:142
 msgid "My account"
 msgstr "Mon compte"
 
-#: templates/base.html:145
+#: corres2math/templates/base.html:145
 msgid "Log out"
 msgstr "Déconnexion"
 
-#: templates/base.html:162
+#: corres2math/templates/base.html:162
 #, python-format
 msgid ""
 "Your email address is not validated. Please click on the link you received "
@@ -1186,23 +1204,23 @@ msgstr ""
 "avez reçu par mail. Vous pouvez renvoyer un mail en cliquant sur <a href="
 "\"%(send_email_url)s\">ce lien</a>."
 
-#: templates/base.html:186
+#: corres2math/templates/base.html:186
 msgid "Contact us"
 msgstr "Nous contacter"
 
-#: templates/base.html:219
+#: corres2math/templates/base.html:219
 msgid "Search results"
 msgstr "Résultats de la recherche"
 
-#: templates/registration/logged_out.html:8
+#: corres2math/templates/registration/logged_out.html:8
 msgid "Thanks for spending some quality time with the Web site today."
 msgstr "Merci d'avoir utilisé la plateforme des Correspondances."
 
-#: templates/registration/logged_out.html:9
+#: corres2math/templates/registration/logged_out.html:9
 msgid "Log in again"
 msgstr "Se reconnecter"
 
-#: templates/registration/login.html:13
+#: corres2math/templates/registration/login.html:13
 #, python-format
 msgid ""
 "You are authenticated as %(user)s, but are not authorized to access this "
@@ -1211,18 +1229,19 @@ msgstr ""
 "Vous êtes connectés en tant que %(user)s, mais n'êtes pas autorisés à "
 "accéder à cette page. Voulez-vous vous reconnecter avec un autre compte ?"
 
-#: templates/registration/login.html:23
+#: corres2math/templates/registration/login.html:23
 msgid "Forgotten your password or username?"
 msgstr "Mot de passe oublié ?"
 
-#: templates/search/search.html:6 templates/search/search.html:11
+#: corres2math/templates/search/search.html:6
+#: corres2math/templates/search/search.html:10
 msgid "Search"
 msgstr "Chercher"
 
-#: templates/search/search.html:16
+#: corres2math/templates/search/search.html:15
 msgid "Results"
 msgstr "Résultats"
 
-#: templates/search/search.html:26
+#: corres2math/templates/search/search.html:25
 msgid "No results found."
 msgstr "Aucun résultat."