I found this guy in the yard yesterday and brought him in the house for the kids. After playing with him they left the lid off and he climbed out and attached himself to the window handle. Perhaps we'll have a butterfly in a couple weeks, If the little kids keep their hands off? I'm thinking of building a little cage around him. Is there anything I need to do for him?

Nope, just watch it , in about 7-9 days it will turn dark, and the next day it will probably come out, if you can open window then you won't need to bring it out side.
I think ours are done here