A blazer and jeans married together are a perfect match. A pair of white canvas low top sneakers will add edginess to this ensemble. A vivid example for anyone who's not sure how to dress as a teenage guy.
Blazer with Jeans Smart Casual Outfits For Men In Their Teens
This pairing of a blazer and jeans is a safe bet for an utterly cool outfit. You could perhaps get a bit experimental with footwear and elevate this ensemble with burgundy leather derby shoes. This combo should encourage anyone who wasn't sure about more elegant looks in his teenage years.