Internet is not an absolutely safe place for children to approach. As a whole, there is no place absolutely safe for children. Of more importance is if parents pay attention to giving proper instruction to guide children how to take advantage of these technologies.

I think that
kids should be older than 13 when they use social media
and 
schools should educate students about online safety
and 
we should not expose personal info like location, phone number...

Meera, Internet is as safe/unsafe as any other physical place. You have to be cautious when browsing, avoiding getting in trouble just like in real life. And be responsible of your deed, writing, and saying.
If you are a good person in real life, don't try to change it in the internet. Be really yourself and teach kids to be themselves too.
:)

I think, what should be done is, just educate the good use of internet from an early age, encouraging young people to spend more time learning, discovering, networking than on useless things.