Facebook Pages or Groups are the place to move if you've hit the friend limit on a personal account and you want to expand.
As a teenager when I was a regular Facebook'er, I was always at the friend limit on my account and would have to remove people before adding new ones... which wasn't a problem seeing as the vast majority of the friends I had on there I didn't know anyhow.

It is depressing to think how much more dangerous the internet has become over the last 10-15 years for teenagers, no way would I ever allow any of my nieces or nephews to randomly add people on Facebook nowadays...