diff --git a/00.brainstorming-pedagogical-teams/45.synthesis-structuring/10.math-tools/40.n4/12.en/textbook.en.md b/00.brainstorming-pedagogical-teams/45.synthesis-structuring/10.math-tools/40.n4/12.en/textbook.en.md
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+---
+title: Brainstorming on the mathematical tools required at each level
+published: true
+routable: true
+visible: false
+lessons:
+    - slug: define-234-mathematical-tools
+      order: 3
+---
+
+#### Define the mathematical tools required at level 4
+
+--------------------------------
+
+with a **first classification to order the brainstorming a little** (counting, geometry, etc.).   
+It *does not presage chapter titles *.
+
+Feel free to create a new classification if necessary.
+
+
+! *xxx*
+!
+
+(XXX-YY)
+...
+
+--------------
+
+(XXX-YY)
+...
+
+-------------- 
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