I am 16 years old, and i have been tinkering for a long, LONG time.
I didn't really get into circuits and stuff until my aunt had an idea for an invention and asked me to prototype it for her. So I learned circuits and stuff over a couple of weeks(and am still learning bit by bit!), and I built it for her, along with a couple of modified versions for it.
and now i'm into high voltage stuff like tesla coils and stuff like that