I saw this idea in blog land this week and decided "why the heck not." It's super easy. Me and my sister in law went to Wal-Mart and bought solid colored shirts for the kids. They were $3 each. We only ended up getting red because most of the blue ones just weren't quite the right color of "4th of July" blue.
All you do is make a bleach mixture of about 70% bleach and 30% water, and pour it into a spray bottle. I cut the stars out on my Cricut, but I've seen it done with lots of other things like glow in the dark stars, those foam sticky stars, I'm sure you could use just about anything. Then we simply laid the stars out on the shirt and sprayed away! We did have one old shirt as practice, just to get the hang of it, but I'm so happy with the end result!
These 2 are Chase and Kardyn's. Then you just throw them in the washer and dryer and tah-dah! I can't wait to see them in them on the 4th of July!
I've also seen some really cute ones done for adults using different stencils. I think I want to try one, so stay tuned!