Seventeen-year-olds Peter Coates and Riley Anderton, of Taieri College, and Hamish Cotter and Daniel Gruppelaar, of John McGlashan College, are part of a Southern-based team.
''I'm really excited,'' Coates, a centre back, said.
''It's a massive opportunity for us coming from club football at Mosgiel to compete against the best age-group players in the world.
''We can see what level we are at compared to the future all-stars of football.''
Anderton, a striker or wing, will use it as a test.
''I will see how I match up against other players from around the world,'' he said.
''It will determine if I pursue football or not.''
Anderton's dream is to become a professional footballer and he is seeking a scholarship to a United States university next year.
''I'm nervous when I think about how I'm going to stand up against the other teams in Ireland, '' he said. ''But I'm excited and confident to see how I will go.''
Coates' dream is to represent New Zealand at a World Cup.
''I'm confident about competing in Ireland because we have a strong team. If we play our own style of football we should do OK.''
The Milk Cup, held annually in Northern Ireland, was first held in 1983.
Many current international footballers have taken part, most notably Charlie Davies, Jonathan Spector, Paul Scholes, Ryan Giggs and Wayne Rooney.
Otago footballers have always formed the bulk of the Southern team.
Southern plays two warm-up games in Manchester, against the Stoke Youth Academy and the Manchester City Development team.
It travels to Belfast on July 6 and its pool games are against CSKA Moscow, Queensland Gold Coast and Bohemena (Ireland).
Mosgiel Football Club, Taieri College and John McGlashan College have supported the boys to make the trip.
