BOSTON — WGBH’s televised choral competition “Sing That Thing!” is heading into its third season.

Registration is open to amateur singing groups from towns and cities in Massachusetts, Maine, New Hampshire, Vermont, Connecticut and Rhode Island. Groups have until early December to register for the show.

Sing That Thing! participants get a chance at exposure on WGBH TV and will interact with music experts from Berklee College of Music, Boston Children’s Chorus and WGBH. Tapings begin this winter.

To audition, groups need to fill out the online form at: http://www.wgbh.org/artsdrama/Sing_That_Thing_Registration.cfm.

Fans can also get involved by signing up to join the live audience: http://www.wgbh.org/artsdrama/Sing_That_Thing_EmailSignUp_AudienceInfo.cfm