Your goal for this stage is to destroy enough blocks while killing all the pigs with a single shot. The angle of the shot doesn’t really matter. All you need to do is to fire it up high enough so that your grabbing power can pass the upper right platform.
Power Activation Point
Activate the power when you get a clear path. You want to grab both the platform as well as some metal blocks.
First Shot Result
The metal blocks that you grab will trigger the bomb on the floating platform. In addition, the platform that you pulled will fall and crush the pigs below. The key to three star for this stage is to try a couple times and your blocks will fall in the right places.