I'll give my opinion coming from someone who is older (31). Most of the time, teens in general, screw around, goof around, dress ridiculous, are loud and obnoxious, do not show respect towards adults, and are misunderstood by adults, etc. You are not even given a chance. People my age or older do not want to be bothered by them let alone sit and watch them fumble through a magic effect that they probably learned on Youtube the night before. Take it as you will, but that describes a good number of young wannabee magicians. They purchase the effect from the local store and within two hours are out at the mall trying to blow people's minds.
Now, if that did not describe you and you consider yourself a mature teen who takes the craft serious, you will still have some hurdles to jump, but you will stand a much better chance than the aforementioned characters. Appearance is a huge selling point to adults. They don't want some dirty looking kid in ripped jeans and a black joker t-shirt to come up to them with a deck of cards. They just don't.
Yes, it is difficult for adults to actually assume or believe that someone in their teens could quite possibly fool them even though I know some of you could fry them with your sleights and skills.
Adults tend to think that you are going to show them some neat little effect you learned from "Uncle Joe" and try to make them look silly. You need to focus more on entertaining them and allowing them to enjoy the moment. Approaching the adults without getting turned down is over half of your battle because there are too many kids out there who are screw offs and have already ruined or "stereotyped" a lot of teens.
You younger guys can think what you want about me but when you get to be older you will see that it is a lot easier to gain attention or respect because you are not a threat to the audience.
O.k. just thought I'd add my two cents.