One way to try and capture that coveted youth market is to make sure there are characters of the right age and personality that the demographic can relate to. Among the many things "Heroes" did right in its first season on NBC, getting the right youthful characters was definitely among them as many on the cast were younger than 30.
In that list were at least three actors who are under 22, thus making them eligible (and eventually nominated) for the SyFy Genre Awards Best Young Actor category.

Noah Gray-Cabey is one of the actors nominated, best known for playing the young Micah who can fix just about anything electronic by simply touching it. While most of the "Heroes" season focused on Ali Larter's split-personality character taking care of him, Micah ended up coming into his own by the season finale using his abilities to help stop Sylar (Zachary Quinto) from blowing up New York City.

One of the most famous faces from "Heroes" who even got a whole advertising campaign featuring her was Hayden Paniettere, the cheerleader, Claire Bennett, which if she was saved, the world was saved.

Panettiere had probably the biggest challenges as an actress, playing some very powerful roles opposite of recurring guest star Thomas Dekker, as her gay/not-so-gay sidekick Zach, who also got nominated. Dekker, who left the show before the end of the first season, appears to have a very promising future as he's set to star in the new Fox series "The Sarah Connor Chronicles" based on the Terminator films.