I did when I first joined two years ago. The site wasn't the same they only allowed 16 yr olds and up and I was 15 and I wasn't about to wait.
I revealed my actual age on a question like this and someone reported me and they were like you're not allowed on this site please come back when you reach the age requirement or something like that. I responded and asked them a question or something and no one ever replied so after a few days I just got back on the site.
Only to find out a few months later they lowered the age limit and I was so pissed. (They also corrected my age so the right one is up there)
As somebody at an age where nobody can take me seriously, I embrace it. If I comment something ridiculous people will probably shrug it off and say "They're just a fifteen year old with a stupid username." I'm bound to say something stupid. I think it's unintelligible when people lie about their age. Why lie about practically irrelevant things?