Quite a tall order, K8.  It depends in part on the ambient temperature and humidity and the heaters available.
You can forget pulp because it would take a lot to get this dry.
Something that could work would be to use eggs - see my article on 'Using Eggs' - because the heat of the cooked egg will help dry the layers of paper.  A bonus is that you also get some lunch!
Once you have cut the layers off the egg and rejoined them, they can be dried in front of a heater or even in a low oven.  They would then be ready for painting, or there might be time to add more shapes with screwed up newspaper and paste.
Do you have access to foamed insulation board?  If so, that might offer more possibilities.
DavidO

I have found that the cellulose wallpaper paste dries more quickly than anything else if you don't make it too thick (and it doesn't need to be thick).  Make it the night before it will be used, and thin it down to the consistency of raw egg whites.

Heaters and fans will help with drying, unless you're in the southwestern part of the U.S., where you will probably just need the fans.

Sue

thanks all for replies! i am still unsure about what to do... it will be winter here (nth of aus) but an outside activity, so heaters probably wont be of any use. hot eggs? hm I'll look into that thanks!

What exactly are you hoping to make in the one day workshop?

A mess, ya silly!