What is the best age to start with Math?

My god son is 5 years old now and I've started to think how should he develop his skills. Should he just be able to read, write and count? Or it's useful to start to work on different specific subjects, like math, for example. Well, I could work with him myself (I used to love math classes at school), but I guess the math tutors would do it more efficiently. I went to the website of Score to check what they can propose. You know, first impression is really important and of course it's two factors: design and navigation. I have to say that it's well done and easy to digest the information, especially I liked a promo video. So, I will consider that school as one of the options!
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