Barr broke through to the first team at the start of the 2006–07 season scoring his first goal for the club on 5 August 2006, in Falkirk's victory over Dunfermline. In December 2006, he was named as SPL Young Player of the Month for December. Barr received his first ever red card on 20 January 2007, for squaring up to Hearts' Andrius Velicka, but the decision was overturned on appeal and Barr was instead credited with a yellow card. The following season Barr was sent off twice: first against Hibernian, being given a second yellow card for throwing the ball away and then against Celtic for receiving a second yellow card.