Wow grinity, are you some kind of god or what ???
A very interesting answer once again ... I will think about all this with DW.
Actually, 7 and 13 are succesive prime numbers ... I did not realize that ... I guess it is just pure coincidence ...
Anyway, we never succeeded in making him count by step of two. HE is defenitely not confortable with the odd an even concept.

Speaking of dislexia, my son's therapist also tols us that dyslexic kids usually have a lot of problem learning multiplication facts. I will take a look to the story-based flashcards (I hope it exists in French too ...) because I tried Anki today, but he found it no fun.

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Sorry for the English !
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