Definitely want to make some capes from adult tee shirts. If cut the neck and add velcro for safety though. No-Sew Superhero Cape from a t-shirt. The post has a tutorial for toilet roll superhero cuffs too.
How to turn old t-shirts into Capes for the Kids! Now we're talking for real. t-shirts cut into the shape of a cape. and you're pretty much done! I'm going to do this w/some white shirts and have the kiddos color them if they want
It's a bird! It's a plane! It's the easiest homemade cape you've ever seen