Super Mario Sunshine/Bianco Hills

3rd Shine
The hillside Cave secret

So, from the start, go to the farthest right you can on this stage, then work your way across the hills to the cave that was shown on the introducing clip. Then, once you get there, you will watch another clip of Shadow Mario taking away FLUDD. Then, work your way across the obstacle course. Other than the blocks twirling around to knock Mario to his death, this is a pretty easy course. Grab the Shine.

6th Shine
The Secret of the Dirty Lake

Once you get to your starting point, you find that the entire lake is polluted. Get your way to the hole at the left side of the lake by going up the big windmill to where it's facing the hole. then use the hover nozzle and go as far as you can. Land on one of those logs and go inside of the hole.

When you get to this obstacle course, you have to jump from rotating platforms, ride turning blocks, and avoid pink arrows shooting at you. This is a pretty hard course, so be prepared to lose a few lives anyway. When you are through, grab the shine.