Well I was dead impressed with the technique and my students next week will be too.
It was quick, easy, not to messy and the results were good.
I used Dylon fabric paints and normal acrylics to try it out and both were very successful . I even bunged them in the washing machine to check that they did remain permanent, which they did.
Tomorrow I will try them on wall paper paste and traditional size.
I've never marbled before because it always seamed a lot of prep but this was sooooooo easy that kids can do it