The town will be chock full of events this week, starting Sunday at 9:30 a.m. with the annual triathlon competition beginning at Memorial Beach. Monday at 7 p.m., the band Group Therapy will play classic rock and Motown hits as part of the Concerts on the Common series. Then on Wednesday, the 57th annual Fourth of July parade kicks off at 9 a.m. at the Route 9/Route 27 plaza, and will travel south on Route 27 until it reaches Route 135 in Natick Center. Visit www.natick4th.org for more information.