The instructions for attire are as follows:
"Please do remember to bring a change of clothes for your child. It doesn't have to be super dressy but of course a step up from sweats would be great. I would say dressing like an evening at a somewhat decent restaurant and not at the Ritz would be a good place to start, maybe business casual for kids :)
Also, picture project will mostly be waist up so you don't have to worry about fancy shoes and all that. If we do some other creative stuff, we will figure out next steps."