Teaching sharpens you. Under-18s: groups only, parents told.

Help someone one or two steps behind you. Explaining it sharpens your own understanding, and mentors reported more satisfaction. With under-18s, keep it in groups or open community spaces, never private one-to-one messages, and tell parents.
P Evidence: promising. Good studies, but small or few. Use it and keep checking.
S Evidence: strong. Large trials or many studies, pointing the same way.
Ghosh & Reio 2013 · DuBois et al. 2011 (youth mentoring works when structured).
Not medical, legal or financial advice.
In The Ecosystem every framework comes with a daily action, a room that checks in, and the full library.