Update textbook.fr.md

00.brainstorming-pedagogical-teams/45.synthesis-structuring/10.math-tools/30.n3/12.en/textbook.fr.md

@@ -12,4 +12,23 @@ lessons:
 
 #### Brainstorming on the mathematical tools required at level 3
 
---------------------------------
+--------------------------------
+
+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)
+...
+
+--------------