For a relaxed casual getup, wear a charcoal crew-neck sweater with grey sweatpants — these pieces go nicely together. Complement your ensemble with white canvas low top sneakers and ta-da: the look is complete. Certainly a goofproof choice when it comes to dressing ideas for teenage guys.
A charcoal crew-neck sweater and khaki corduroy chinos are a good outfit worth incorporating into your current casual lineup. For something more on the daring side to complement this look, throw white canvas low top sneakers into the mix. This combo is most probably exactly what you're looking for as a teen.