We asked our readers: What should be the age of conversion? Is 18 too young? Here are several replies. (We'll be posting them one by one.)
My advice to anyone, young or old, would be to follow your curiosity, trust your intuition, keep your eyes & heart open for signs and mentors/teachers, and take time to reflect on what is missing and what you want or hope to gain.
I don't think 18 is too young. Lots of folks make big changes at that age. On the other hand, he could take classes and otherwise educate & expose himself to this religion for months or years, then decide. I took 5 years of classes, during which we shopped a few different religions and congregations, before deciding on Judaism, then finding the right rabbi for me.