Roberts had an extremely successful and influential youth career for the Australian national team. Roberts made her international debut at the 2009 FIBA Oceania Under-16 Championship in Brisbane, Australia, where she took home Gold and secured Australia's place at the inaugural Under-17 World Championship the following year. Roberts would go on to represent Australia at the FIBA World Championship in France where Australia placed seventh. At this tournament Roberts averaged 16.1 points per game. She then transitioned to represent the Gems at the 2011 FIBA Under-19 World Championship in Chile. At this tournament she was the highest scorer in any single game, scoring 41 points against Japan. Despite averaging 15.9 points per game on a strong Australian team, the team narrowly missed out on bronze, placing fourth.