Effortlessly blurring the line between dapper and casual, this pairing of a white and navy horizontal striped crew-neck t-shirt and beige chinos can easily become one of your go-tos. A great pair of white canvas low top sneakers ties this ensemble together. Naturally, it's easier to work through a super hot summertime afternoon in a easy and breezy ensemble like this. And if we're talking casual dressing ideas for teen boys, this ensemble looks cool on most gentlemen.