I marbleized paper once with kindergaterners. We used the less toxic liquid
starch/acrylic paint method, and fairly thin paper ( we were going to make
notecards or stationery). It turned out looking beautiful, but I found that
it made the paper very stiff and curled at the edges. Maybe a different type
of paper, or different drying method, would yeild better results. Definitely
worth experimenting with!