I know it's a little late in the year to teach them a lesson, but I
would not continue with the papier-mache. I once had the same problem
with the same project. We had studied "Mask" in great depth and I
couldn't see dropping it completely, so I just told the class that I had
misjudged them. They weren't quite ready for such a project. It
required a higher maturity level that what they had demonstrated. Then
I got the crayons out and had them to design a mask and color it. End
of project. The next time we did a "highly active" project they were
telling each other to calm down and act right so I wouldn't cancel the
project.