I once took a papermaking class. I don't know how practical the following
technique would be in the classroom, but we had fun with it. We took a piece of
muslin, poured (dry, clean) kitty litter on it, gathered it at the top and
tied it off--so it looked like a ball--about the size of a grapefruit. We hung
these from a clothesline and formed sheets of paper and draped them over the
ball. After they dried, we poured the kitty litter out, removed the muslin,
and there was the bowl. I guess you could do the same thing with paper pulp.