This is part 34 of my 100% Super Mario 3D World Walkthrough. This part includes World Mushroom levels 7 and Mystery House. Below are the times for the green stars and stamp in this stage.

00:15 World Mushroom-7 - Broken Blue Bully Belt
00:48 - Green Star #1
01:32 - Green Star #2
02:33 - Green Star #3
03:40 World Mushroom-Mystery House - Mystery House Brawl