diff --git a/01.curriculum/01.physics-chemistry-biology/03.Niv3/02.geometrical-optics/01.geometrical-optics-general/02.geometrical-optics-validity/01.geometrical-optics-domain-of-validity-main/textbook.en.md b/01.curriculum/01.physics-chemistry-biology/03.Niv3/02.geometrical-optics/01.geometrical-optics-general/02.geometrical-optics-validity/01.geometrical-optics-domain-of-validity-main/textbook.en.md
index c1e2d015b..811fc65bd 100644
--- a/01.curriculum/01.physics-chemistry-biology/03.Niv3/02.geometrical-optics/01.geometrical-optics-general/02.geometrical-optics-validity/01.geometrical-optics-domain-of-validity-main/textbook.en.md
+++ b/01.curriculum/01.physics-chemistry-biology/03.Niv3/02.geometrical-optics/01.geometrical-optics-general/02.geometrical-optics-validity/01.geometrical-optics-domain-of-validity-main/textbook.en.md
@@ -4,9 +4,10 @@ published: false
 visible: false
 lessons:
     - slug: geometrical-optics-domain-of-validity
+      order: 1
 ---
 
-###Domaine de validité de l'optique géométrique
+### Domaine de validité de l'optique géométrique
 
 L’<strong>optique géométrique</strong><em> modélise le comportement de la lumière avec les concepts de rayon lumineux, d'indice de réfraction et un principe de base : le principe de Fermat appliqué à la trajectoire des rayons lumineux</em>
 Elle permet de <em>comprendre puis maîtriser la formation des images</em> par des <strong>systèmes optiques de dimensions caractéristiques a grandes devant la longueur d’onde &lambda; de la lumière (a &#8811  &lambda;). </strong> 
diff --git a/01.curriculum/01.physics-chemistry-biology/03.Niv3/02.geometrical-optics/01.geometrical-optics-general/02.geometrical-optics-validity/02.geometrical-optics-domain-of-validity-overview/cheatsheet.en.md b/01.curriculum/01.physics-chemistry-biology/03.Niv3/02.geometrical-optics/01.geometrical-optics-general/02.geometrical-optics-validity/02.geometrical-optics-domain-of-validity-overview/cheatsheet.en.md
index 1a11aa03f..d50eccdf4 100644
--- a/01.curriculum/01.physics-chemistry-biology/03.Niv3/02.geometrical-optics/01.geometrical-optics-general/02.geometrical-optics-validity/02.geometrical-optics-domain-of-validity-overview/cheatsheet.en.md
+++ b/01.curriculum/01.physics-chemistry-biology/03.Niv3/02.geometrical-optics/01.geometrical-optics-general/02.geometrical-optics-validity/02.geometrical-optics-domain-of-validity-overview/cheatsheet.en.md
@@ -5,6 +5,7 @@ published: true
 visible: false
 lessons:
     - slug: geometrical-optics-domain-of-validity
+      order: 2
 ---
 
 ### The optics for everyday life
diff --git a/01.curriculum/01.physics-chemistry-biology/03.Niv3/02.geometrical-optics/01.geometrical-optics-general/02.geometrical-optics-validity/03.geometrical-optics-domain-of-validity-beyond/annex.en.md b/01.curriculum/01.physics-chemistry-biology/03.Niv3/02.geometrical-optics/01.geometrical-optics-general/02.geometrical-optics-validity/03.geometrical-optics-domain-of-validity-beyond/annex.en.md
index 807ea1ee8..c4cd8cc29 100644
--- a/01.curriculum/01.physics-chemistry-biology/03.Niv3/02.geometrical-optics/01.geometrical-optics-general/02.geometrical-optics-validity/03.geometrical-optics-domain-of-validity-beyond/annex.en.md
+++ b/01.curriculum/01.physics-chemistry-biology/03.Niv3/02.geometrical-optics/01.geometrical-optics-general/02.geometrical-optics-validity/03.geometrical-optics-domain-of-validity-beyond/annex.en.md
@@ -2,6 +2,7 @@
 title: 'new course : beyond'
 lessons:
     - slug: geometrical-optics-domain-of-validity
+      order: 3
 ---
 
 ! *YOUR  CHALLENGE*  :  look at the picture, and think of the right answers to the following questions