Wet yarn with glue, arrange on wax paper, allow to dry~Moon~by Elaine Carstairs Beautiful. I suspect the children would have a blast creating this, and then tracing it. - shadow art is very contemporary!
add wood wallpaper to the kick plates of the stairs. Those rolls are expensive but you would only need one. Not practical with white treads though, it will be stuffed up from black shoe soles in no time.