Victoria Justice Actor Daniella Monet Actor Leon Thomas III Actor Elizabeth Gillies Actor Avan Jogia Actor Ariana Grande Actor Matt Bennett Actor Keith Allan Michael Guest Star Shayna Amin Little Girl Guest Star Austin Anderson Drummer Guest Star Jill Basey Sikowitz's Mom Guest Star Skyler Bible Keyboardist Guest Star Nick Bush Mall Manager Guest Star Tim Chiou Record Producer Guest Star Mason Cook Little Harry Guest Star Ava Marie Easter Little Girl Guest Star Caden Michael Gray Sinjin's Friend 1 Guest Star Molly Jackson Little Stephanie Guest Star Eric Lange Mr. Sikowitz Guest Star Thomas Mikusz Kevin Chase Guest Star David Militello Devon Guest Star Veno Miller Bassist Guest Star Lane Napper Lane Guest Star Michael Eric Reid Sinjin Guest Star Lucas Ross Guitarist Guest Star Alec Tokar Sinjin's Friend 2 Guest Star Dan Schneider Executive Producer