In 2007, van Riemsdyk returned to the World U18 Championships, tying for the tournament lead with 12 points and helping take Team USA to a silver medal. van Riemsdyk was named both the top forward in the tournament and the most valuable player, and he received a selection to the tournament All-Star team. 2007 was also the year of van Riemsdyk's first World Junior Ice Hockey Championships (WJC) appearance. He played in four games of the series, recording one goal, and Team USA took home the bronze medal. van Riemsdyk also appeared at the 2008 and 2009 WJC tournaments. Although Team USA failed to medal at both tournaments, van Riemsdyk led all players in scoring in 2008, with 11 points in six games, and he put up another 10 points the following year.