diff --git a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/01.new-course-main/textbook.en.md b/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/01.new-course-main/textbook.en.md
deleted file mode 100644
index db2c0a73c..000000000
--- a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/01.new-course-main/textbook.en.md
+++ /dev/null
@@ -1,7 +0,0 @@
----
-title: 'new course : main'
-published: false
-visible: false
----
-
-new course : main
\ No newline at end of file
diff --git a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/01.new-course-main/textbook.es.md b/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/01.new-course-main/textbook.es.md
deleted file mode 100644
index b43652c4a..000000000
--- a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/01.new-course-main/textbook.es.md
+++ /dev/null
@@ -1,7 +0,0 @@
----
-title: 'nuevo curso: principal'
-published: false
-visible: false
----
-
-nuevo curso: principal
\ No newline at end of file
diff --git a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/01.new-course-main/textbook.fr.md b/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/01.new-course-main/textbook.fr.md
deleted file mode 100644
index ceac940f2..000000000
--- a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/01.new-course-main/textbook.fr.md
+++ /dev/null
@@ -1,7 +0,0 @@
----
-title: 'nouveau cours : principal'
-published: false
-visible: false
----
-
-nouveau cours : principal
\ No newline at end of file
diff --git a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/02.new-course-overview/axe_opt.gif b/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/02.new-course-overview/axe_opt.gif
deleted file mode 100644
index fcc23d8b6..000000000
Binary files a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/02.new-course-overview/axe_opt.gif and /dev/null differ
diff --git a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/02.new-course-overview/cheatsheet.en.md b/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/02.new-course-overview/cheatsheet.en.md
deleted file mode 100644
index 14ef58c77..000000000
--- a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/02.new-course-overview/cheatsheet.en.md
+++ /dev/null
@@ -1,9 +0,0 @@
----
-title: 'new course  : overview'
-published: false
-visible: false
----
-
-new course  : overview
-
-![](axe_opt.gif)
\ No newline at end of file
diff --git a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/02.new-course-overview/cheatsheet.es.md b/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/02.new-course-overview/cheatsheet.es.md
deleted file mode 100644
index 426d95e56..000000000
--- a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/02.new-course-overview/cheatsheet.es.md
+++ /dev/null
@@ -1,9 +0,0 @@
----
-title: 'nuevo curso : síntesis'
-published: false
-visible: false
----
-
-nuevo curso : síntesis
-
-![](axe_opt.gif)
\ No newline at end of file
diff --git a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/02.new-course-overview/cheatsheet.fr.md b/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/02.new-course-overview/cheatsheet.fr.md
deleted file mode 100644
index 38e0a61fb..000000000
--- a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/02.new-course-overview/cheatsheet.fr.md
+++ /dev/null
@@ -1,9 +0,0 @@
----
-title: 'nouveau cours : synthèse'
-published: false
-visible: false
----
-
-nouveau cours : synthèse
-
-![](axe_opt.gif)
\ No newline at end of file
diff --git a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/03.new-course-beyond/annex.en.md b/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/03.new-course-beyond/annex.en.md
deleted file mode 100644
index 808147926..000000000
--- a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/03.new-course-beyond/annex.en.md
+++ /dev/null
@@ -1,61 +0,0 @@
----
-title: 'new course : beyond'
-published: false
-visible: false
----
-
-! *YOUR  CHALLENGE*  :  look at the picture, and think of the right answers to the following questions
-!
-! _Do not look at the answer, take time to think, a few days if necessary. The time to build your mental representation of the phenomenon, to formulate it in words is important, a thousand times more important than the ephemeral instant where you read the fews words of the solution._
-!
-! <details markdown=1>
-! <summary>
-! INDICE "key word"
-! </summary>
-! diffusion
-! </details>
-! <details markdown=1>
-! <summary>
-! ANSWER
-! </summary>
-! diffusion
-! </details>
-
-
-!!!! *DIFFICULT POINT* (contribute, or indicate a difficult point of understanding)
-!!!!
-
-!! *BEYOND* (to contribute)
-!!
-
-!! *CULTURAL POINT* (contributor)
-!!
-
-!!! *DO  YOU  MASTER ?*
-!!! <details markdown=1>
-!!! <Summary>
-!!! Describe the test
-!!! </summary>
-!!! The text of the test (and its images, figures, audio, video, etc ...)
-!!!
-!!! Question text
-!!! <details markdown=1>
-!!! <summary>
-!!! Answer choice 1
-!!! </summary>
-!!! Text if this answer 1 is chosen
-!!! </details>
-!!! <details markdown=1>
-!!! <summary>
-!!! Answer choice 2
-!!! </summary>
-!!! Text if this answer 2 is chosen
-!!! </details>
-!!! <!--possibility to add answers, questions-->
-!!! -----
-!!! <details markdown=1>
-!!! <summary>
-!!! Complete solution.
-!!! </summary>
-!!! text of the solution
-!!! </details>
diff --git a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/03.new-course-beyond/annex.es.md b/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/03.new-course-beyond/annex.es.md
deleted file mode 100644
index 4573be9bd..000000000
--- a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/03.new-course-beyond/annex.es.md
+++ /dev/null
@@ -1,60 +0,0 @@
----
-title: 'nuevo curso: más allá'
-published: false
-visible: false
----
-
-! *TU DESAFÍO*  :  Mire la imagen y encuentre las respuestas correctas a las siguientes preguntas.
-!
-! _No mire la respuesta, tómese el tiempo para pensar, unos días si es necesario. El momento de construir tu representación mental del fenómeno, de formular con palabras esta representación es importante, mil veces más importante que el momento efímero de leer las pocas palabras de la solución._
-!
-! <details markdown=1>
-! <summary>
-! ÍNDICE "palabra clave"
-! </summary>
-! xxx
-! </details>
-! <details markdown=1>
-! <summary>
-! RESPUESTA
-! </summary>
-! xxx
-! </details>
-
-!!!! *PUNTO DIFÍCIL* (contribuya o indique los puntos difíciles que deben tomarse nuevamente)
-!!!!
-
-!! *MÁS ALLÁ* (contribuir)
-!!
-
-!! *ESCAPE CULTURAL* (contribuir)
-!!
-
-!!! *MAÎTRISES-TU ?*
-!!! <details markdown = 1>
-!!! <summary>
-!!! Describe la prueba
-!!! </summary>
-!!! Texto de prueba (y sus imágenes, figuras, audio, video, etc ...)
-!!! ![una figura para la prueba] (nombre de archivo)
-!!!
-!!! Prueba la pregunta
-!!! <details markdown=1>
-!!! <summary>
-!!! Respuesta opción 1
-!!! </summary>
-!!! Texto si se elige la respuesta 1
-!!! </details>
-!!! <details markdown=1>
-!!! <summary>
-!!! Respuesta opción 2
-!!! </summary>
-!!! Texto si se elige la respuesta 2
-!!! </details>
-!!! <!--Posibilidad de añadir respuestas, preguntas-->
-!!! <details markdown=1>
-!!! <summary>
-!!! Solucion completa
-!!! </summary>
-!!! Texto de la solución.
-!!! </details>
diff --git a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/03.new-course-beyond/annex.fr.md b/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/03.new-course-beyond/annex.fr.md
deleted file mode 100644
index 04d240360..000000000
--- a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/03.new-course-beyond/annex.fr.md
+++ /dev/null
@@ -1,61 +0,0 @@
----
-title: 'nouveau cours : au-delà'
-published: false
-visible: false
----
-
-! *TON  DEFI*  :   
-!
-! _Ne regarde pas la réponse, prends le temps de réfléchir, quelques jours si nécessaire. Le temps de construire ta représentation mentale du phénomène, de formuler en mots cette réflexion est important, un millier de fois plus important que l'instant éphémère de la lecture des quelques mots de la solution._
-!
-! <details markdown=1>
-! <summary>
-! INDICE "mot clé"
-! </summary>
-! xxx
-! </details>
-! <details markdown=1>
-! <summary>
-! RÉPONSE
-! </summary>
-! xxx
-! </details>
-
-!!!! *POINT  DIFFICILE* (contribuer, ou indiquer les points difficiles qui méritent d'être repris)
-!!!!
-
-!! *AU-DELÀ* (contribuer)
-!!
-
-!! *ÉCHAPPÉE CULTURELLE* (contribuer)
-!!
-
-!!! *MAÎTRISES-TU ?*
-!!! <details markdown = 1>
-!!! <summary>
-!!! Descrire le test
-!!! </summary>
-!!! Texte du test (et ses images, figures, audio, video, etc ...)
-!!! ! [a figure for the test] (file-name)
-!!!
-!!! Texte de la question
-!!! <details markdown=1>
-!!! <summary>
-!!! Choix de réponse 1
-!!! </summary>
-!!! Texte si la réponse 1 est choisie
-!!! </details>
-!!! <details markdown=1>
-!!! <summary>
-!!! Choix de réponse 2
-!!! </summary>
-!!! Texte si la réponse 2 est choisie
-!!! </details>
-!!! <!--possibility to add answers, questions-->
-!!! -----
-!!! <details markdown=1>
-!!! <summary>
-!!! Solution complète
-!!! </summary>
-!!! Texte de la solution
-!!! </details>
diff --git a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/04.new-course-parallel-1/default.en.md b/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/04.new-course-parallel-1/default.en.md
deleted file mode 100644
index 3d4d0456d..000000000
--- a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/04.new-course-parallel-1/default.en.md
+++ /dev/null
@@ -1,54 +0,0 @@
----
-title: 'new course : parallel 1'
-published: false
-visible: false
-content:
-    items: '- ''@self.children'''
-    order:
-        by: date
-        dir: desc
-    limit: '5'
-    pagination: '1'
-    url_taxonomy_filters: '1'
-hero_classes: ''
-hero_image: ''
----
-
-new course : parallel 1
-
-#####for parallel or other level course :
-It will be possible to redirect towards an other page in the m3p2 cursus.
-Or to write here some paragraphes separated by html from an other pages, I think.
-Or write here a completely new parallel course
-
-For the moment, please wait.
-
-Ya es possible hacer
-I can here :
-- write a full "parallel 1 course" if required
-- or add add a few word about a "course parallel 1" that is written somewhere in "pages/curriculum/..."
-- or do nothing.
-
-    Go 
-    
-    [there](http://localhost:8000/en/m3p2-curriculum/physics-chemistry-biology/niv3/Geometrical-optics/geometrical-optics-general/geometrical-optics-validity/geometrical-optics-domain-of-validity-overview)
-    
-    [Current chapter](.)
-    [Parent chapter](..)
-    [Sibling chapter](../another-chapter)
-    [Child chapter](chapter)
-    [Anchor in the page](#slug-of-header)
-
-<details markdown=1>
-<summary>
-TOWARDS parallel 1, if their are several
-</summary>
-This is a text
-```math
-f\colon\left\{\begin{aligned}\mathbb{R}_4[X]&\longrightarrow\mathbb{R}_4[X] \\
-P&\longmapsto P’\end{aligned}\right.
-\qquad
-g\colon\left\{\begin{aligned}\mathbb{R}_2[X]&\longrightarrow\mathbb{R}_2[X] \\
-P&\longmapsto XP’+P\end{aligned}\right.
-```
-</details>
diff --git a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/04.new-course-parallel-1/default.es.md b/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/04.new-course-parallel-1/default.es.md
deleted file mode 100644
index 1c10d6f37..000000000
--- a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/04.new-course-parallel-1/default.es.md
+++ /dev/null
@@ -1,25 +0,0 @@
----
-title: 'nuevo curso : paralelo 1'
-published: false
-visible: false
-hero_classes: ''
-hero_image: ''
-content:
-    items: '- ''@self.children'''
-    limit: '5'
-    order:
-        by: date
-        dir: desc
-    pagination: '1'
-    url_taxonomy_filters: '1'
----
-
-nuevo curso : paralelo 1
-
-
-##### para un curso paralelo o de otro nivel:
-Será (ya es) posible redirigir hacia otra página en el cursus m3p2.
-O escribir aquí algunos párrafos separados por html de otras páginas, creo.
-Tambien podemos aquí escribir un curso paralelo o de otro nivel completamente nuevo
-
-*Por el momento, por favor espere*
\ No newline at end of file
diff --git a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/04.new-course-parallel-1/default.fr.md b/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/04.new-course-parallel-1/default.fr.md
deleted file mode 100644
index 8862a5460..000000000
--- a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/04.new-course-parallel-1/default.fr.md
+++ /dev/null
@@ -1,24 +0,0 @@
----
-title: 'nouveau cours : parallèle 1'
-published: false
-visible: false
-hero_classes: ''
-hero_image: ''
-content:
-    items: '- ''@self.children'''
-    limit: '5'
-    order:
-        by: date
-        dir: desc
-    pagination: '1'
-    url_taxonomy_filters: '1'
----
-
-nouveau cours : parallèle 1
-
-##### pour un cours parallèle ou d'un autre niveau
-Il sera posible (cela l'est déjà) de rediriger automatiquement vers une autre page dans le cursus m3p2.
-Ou d'écrire quelques paragraphes avec entre du html emprunter à d'autres pages je pense.
-On peut toujours aussi écrire ici un cours parallèle ou d'un autre niveau complétement nouveau
-
-*Pour le moment,, attendre, SVP*
\ No newline at end of file
diff --git a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/05.new-course-parallel-2/form.en.md b/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/05.new-course-parallel-2/form.en.md
deleted file mode 100644
index 99c006620..000000000
--- a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/05.new-course-parallel-2/form.en.md
+++ /dev/null
@@ -1,14 +0,0 @@
----
-title: 'new course : parallel 2'
-published: false
-visible: false
----
-
-new course : parallel 2
-
-#####for parallel or other level course :
-It will be possible to redirect towards an other page in the m3p2 cursus.
-Or to write here some paragraphes separated by html from an other pages, I think.
-Or write here a completely new parallel course
-
-For the moment, please wait.
\ No newline at end of file
diff --git a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/05.new-course-parallel-2/form.es.md b/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/05.new-course-parallel-2/form.es.md
deleted file mode 100644
index b7c82c4e2..000000000
--- a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/05.new-course-parallel-2/form.es.md
+++ /dev/null
@@ -1,14 +0,0 @@
----
-title: 'nuevo curso : paralelo 2'
-published: false
-visible: false
----
-
-nuevo curso : paralelo 2
-
-##### para un curso paralelo o de otro nivel:
-Será (ya es) posible redirigir hacia otra página en el cursus m3p2.
-O escribir aquí algunos párrafos separados por html de otras páginas, creo.
-Tambien podemos aquí escribir un curso paralelo o de otro nivel completamente nuevo
-
-*Por el momento, por favor espere*
\ No newline at end of file
diff --git a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/05.new-course-parallel-2/form.fr.md b/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/05.new-course-parallel-2/form.fr.md
deleted file mode 100644
index 2c1f54629..000000000
--- a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/05.new-course-parallel-2/form.fr.md
+++ /dev/null
@@ -1,15 +0,0 @@
----
-title: 'nouveau cours : parallèle 2'
-published: false
-visible: false
----
-
-nouveau cours : parallèle 2
-
-##### pour un cours parallèle ou d'un autre niveau
-Il sera posible (cela l'est déjà) de rediriger automatiquement vers une autre page dans le cursus m3p2.
-Ou d'écrire quelques paragraphes avec entre du html emprunter à d'autres pages je pense.
-On peut toujours aussi écrire ici un cours parallèle ou d'un autre niveau complétement nouveau
-
-*Pour le moment,, attendre, SVP*
-
diff --git a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/06.course-level-down/page.en.md b/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/06.course-level-down/page.en.md
deleted file mode 100644
index bf23bba6c..000000000
--- a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/06.course-level-down/page.en.md
+++ /dev/null
@@ -1,16 +0,0 @@
----
-title: 'course : level-1'
-published: false
-visible: false
----
-
-course : level-1 
-- or level+1 if current level = 1
-- or level-2  if current level = 4
-
-#####for parallel or other level course :
-It will be possible to redirect towards an other page in the m3p2 cursus.
-Or to write here some paragraphes separated by html from an other pages, I think.
-Or write here a completely new parallel course
-
-For the moment, please wait.
\ No newline at end of file
diff --git a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/06.course-level-down/page.es.md b/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/06.course-level-down/page.es.md
deleted file mode 100644
index 9da25c5b5..000000000
--- a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/06.course-level-down/page.es.md
+++ /dev/null
@@ -1,16 +0,0 @@
----
-title: 'curso : nivel-1'
-published: false
-visible: false
----
-
-curso : nivel-1
-- or level+1 if current level = 1
-- or level-2  if current level = 4
-
-##### para un curso paralelo o de otro nivel:
-Será (ya es) posible redirigir hacia otra página en el cursus m3p2.
-O escribir aquí algunos párrafos separados por html de otras páginas, creo.
-Tambien podemos aquí escribir un curso paralelo o de otro nivel completamente nuevo
-
-*Por el momento, por favor espere*
\ No newline at end of file
diff --git a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/06.course-level-down/page.fr.md b/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/06.course-level-down/page.fr.md
deleted file mode 100644
index 7d17b4874..000000000
--- a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/06.course-level-down/page.fr.md
+++ /dev/null
@@ -1,16 +0,0 @@
----
-title: 'cours : niveau-1'
-published: false
-visible: false
----
-
-cours : niveau-1
-- or level+1 if current level = 1
-- or level-2  if current level = 4
-
-##### pour un cours parallèle ou d'un autre niveau
-Il sera posible (cela l'est déjà) de rediriger automatiquement vers une autre page dans le cursus m3p2.
-Ou d'écrire quelques paragraphes avec entre du html emprunter à d'autres pages je pense.
-On peut toujours aussi écrire ici un cours parallèle ou d'un autre niveau complétement nouveau
-
-*Pour le moment,, attendre, SVP*
\ No newline at end of file
diff --git a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/07.course-level-up/portal.en.md b/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/07.course-level-up/portal.en.md
deleted file mode 100644
index 6ed88eb9d..000000000
--- a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/07.course-level-up/portal.en.md
+++ /dev/null
@@ -1,20 +0,0 @@
----
-title: 'course : level+1'
-published: false
-visible: false
-hero_classes: ''
-hero_image: ''
----
-
-course : level+1
-
-or level+2 if current level=1
-
-or level-1 if current level=4
-
-#####for parallel or other level course :
-It will be possible to redirect towards an other page in the m3p2 cursus.
-Or to write here some paragraphes separated by html from an other pages, I think.
-Or write here a completely new parallel course
-
-For the moment, please wait.
\ No newline at end of file
diff --git a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/07.course-level-up/portal.es.md b/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/07.course-level-up/portal.es.md
deleted file mode 100644
index 007505639..000000000
--- a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/07.course-level-up/portal.es.md
+++ /dev/null
@@ -1,16 +0,0 @@
----
-title: 'curso : nivel+1'
-published: false
-visible: false
----
-
-curso : nivel+1
-or level+2 if current level=1
-or level-1 if current level=4
-
-##### para un curso paralelo o de otro nivel:
-Será (ya es) posible redirigir hacia otra página en el cursus m3p2.
-O escribir aquí algunos párrafos separados por html de otras páginas, creo.
-Tambien podemos aquí escribir un curso paralelo o de otro nivel completamente nuevo
-
-*Por el momento, por favor espere*
\ No newline at end of file
diff --git a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/07.course-level-up/portal.fr.md b/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/07.course-level-up/portal.fr.md
deleted file mode 100644
index ea7ca6055..000000000
--- a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/07.course-level-up/portal.fr.md
+++ /dev/null
@@ -1,16 +0,0 @@
----
-title: 'cours : niveau+1'
-published: false
-visible: false
----
-
-cours : niveau+1
-or level+2 if current level=1
-or level-1 if current level=4
-
-##### pour un cours parallèle ou d'un autre niveau
-Il sera posible (cela l'est déjà) de rediriger automatiquement vers une autre page dans le cursus m3p2.
-Ou d'écrire quelques paragraphes avec entre du html emprunter à d'autres pages je pense.
-On peut toujours aussi écrire ici un cours parallèle ou d'un autre niveau complétement nouveau
-
-*Pour le moment,, attendre, SVP*
\ No newline at end of file
diff --git a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/aef-optics-test4.mov b/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/aef-optics-test4.mov
deleted file mode 100644
index fac235785..000000000
Binary files a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/aef-optics-test4.mov and /dev/null differ
diff --git a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/topic.en.md b/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/topic.en.md
deleted file mode 100644
index f125c762c..000000000
--- a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/topic.en.md
+++ /dev/null
@@ -1,6 +0,0 @@
----
-title: 'Paraxial modeling of centered optical systems'
-published: false
-visible: false
----
-
diff --git a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/topic.es.md b/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/topic.es.md
deleted file mode 100644
index 09216e914..000000000
--- a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/topic.es.md
+++ /dev/null
@@ -1,6 +0,0 @@
----
-title: 'Modélisation paraxiale des systèmes optiques centrés'
-published: false
-visible: false
----
-
diff --git a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/topic.fr.md b/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/topic.fr.md
deleted file mode 100644
index 09216e914..000000000
--- a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/04.paraxial-optics-centered-systems/topic.fr.md
+++ /dev/null
@@ -1,6 +0,0 @@
----
-title: 'Modélisation paraxiale des systèmes optiques centrés'
-published: false
-visible: false
----
-