Hi Steve;
I am presently doing research primarily, but I do mentor middle- and high-school students (for science-fair projects, for example), and have advised graduate students and post-doctoral researchers -- they are "new" scientists. I do miss being in a classroom, though! Still, I do also give presentations in elementary, middle, and high schools so I do get to interact with a lot of students, just not as a formal classroom professor right now.
I got my PhD in 1995, but was an active "science-minded kid" forever before that. A PhD may demonstrate a certain degree of training, but many people get similar training "on the job" and be extremely productive.
Cheers, -KD