Yes, at around these ages, I used the Internet to study enlightenment, the FInacnial Markets such at the Foriegn exchange market.
Half of the reason people call me Genius comes directly from the internet.
Just raise your child properly, be conscious of what he learns from his peers at school, and you should be ok.
I wasn't supervised, I was just mature from an early age, and even though I had knowledge of the explicit material on the internet which came from my social environment 'SCHOOL'
I still used the internet for something better.
And trust me, if you think your kid at the age of 13 doesn't know a thing about porn, and he goes to school, then your in for a surprise. (Most of the time).
You should let your child look up to you as family and not the state or school, from which he spends most of his time with!!!
Please do read my article here.